From the perspective of social relationships, this study extends the understanding of employee voice by examining voice outcomes, especially a voicer’s influence in their work team. In particular, we explore how two different social relationships, LMX and peer relationship, separately and jointly affect the ‘voice-influence’ relationship. Drawing on social network theory, we propose that higher LMX and central positions in peer networks  strengthen the positive impact of voice on individual influence. From a sample of 128 employees from three firms in South Korea, we found that two types of voice (promotive and prohibitive) are positively related with individual influence. This study also found that LMX strengthened the positive effect of promotive voice on a voicer’s influence. Moreover, LMX and peer relationship jointly affect the voice-influence relationship as follows: (1) a voicer with a high LMX-high centrality (in the peer network) is most influential within their team, (2) as for a low LMX-high centrality member, speaking up rather decreases individual influence. These results suggest that voice outcome is not unilateral. Rather, whose voice it is and where a voicer stands may matter more. We discussed the theoretical and practical implications of these findings in employee voice research. Employee voice is a key driver of group or organizational success and constructive change ,2,3. GivTo enable employees to speak up, we need to understand the social outcomes of voice behavior and the mechanism through which it is produced. Several studies have emphasized that voice increases the status, power, and personal influence of a voicer ,8. ConseFurthermore, employee voice is a social phenomenon. It has a target or audience to speak to. Even voice conveying the same content can be recognized or evaluated differently by the supervisor and colleagues in the workplace ,7,10,11.In light of this stream of research, we examine the moderating role of leader–member exchange (LMX) and peer relationships in the process of determining the voice outcome. Drawing on social network theory, we especially focus on the separate and joint effects of LMX and peer relationships. Although the main effects of LMX have been well addressed ,16 in voMoreover, this study goes further to examine the combined effects of these two social relationships. In a real work team, a member’s relationships with the formal leader and with other members (excluding the leader) are inextricably interwoven . SeveralIn conclusion, our research question aims to better understand under what conditions employee voice enhances voicers’ influences in the workplace. Regardless of voice content, voice outcomes may be beneficial or harmful to voice-performers, along with the social context in which they are located. We advance the theory of voice outcomes by examining the possible combination of LMX and informal peer relationships, which in turn delineates the boundary conditions of harvesting voice outcomes for individuals. Thus, we attempt to answer the question of whose voice will be heard, appreciated, or devalued within a team, and understand the factors amplifying or mitigating the impact of voice.Employee voice, referring to the discretionary communication of improvement-oriented suggestions, ideas, options, or concerns, is a critical component in enhancing organizational or work-unit functioning ,22,23. TFurther, the nonconforming nature of voice behavior can illuminate a voicer’s competence. Nonconformity  directs the focus of the group to the contributions made by the voicer . From thHypothesis 1. (H1).Voice behavior is positively related to individual influence within a team.Voice behavior is target-sensitive, implying that peers’ perspectives of voice and that of the supervisor play a critical role when individuals decide whether to speak up or not . TherefoFirst, the relationship with the leader can impact the voice-influence relationship. LMX is the quality of relationships between a supervisor and his or her subordinates . BecauseIn addition, employees with high LMX not only receive valuable resources from the leader but also inflated performance ratings because of leniency bias resulting from the leader’s intention to reciprocate ,40. GiveHypothesis 2. (H2).LMX moderates the relationship between voice behavior and individual influence within a team, such that the positive relationship is stronger when a voicer has higher LMX.Peer relationships have gained attention as most organizations now pursue a more horizontal structure . With thHypothesis 3. (H3).Peer relationships moderate the relationship between voice behavior and individual influence within a team, such that the positive relationship is stronger when a voicer has high-quality peer relationships .In this study, we maintain that the two aforementioned social relationships, LMX and peer relationships, have their own interaction effects on individual influence with voice behavior in a team. However, previous social exchange research has suggested that the relationship between the leader and coworkers is inextricably interwoven within a work team ,49. In tSpecifically, an employee’s voice may be more strongly associated with their influence when it is combined with both high LMX and quality peer relationships. Employees with high LMX and high centrality in friendship networks can receive specific supports and opportunities necessary for effective job performance through unique relationships with the supervisor  and haveNext, although prior research has suggested that employees with high LMX could be evaluated positively by supervisors ,54, voicHypothesis 4. (H4).LMX and peer relationships jointly moderate the relationship between voice behavior and individual influence.Hypothesis 4a. (H4a).With high-quality peer relationships , the relationship between voice behavior and individual influence is stronger for a voicer with high LMX than for a voicer with low LMX.Hypothesis 4b. (H4b).With low-quality peer relationships , the relationship between voice behavior and individual influence is weaker for a voicer with high LMX than for a voicer with low LMX.The overall research model is illustrated in To test our hypotheses, we collected data from 3 organizations in South Korea. These organizations were an IT company, a manufacturing and retail company, and a public enterprise. Before distributing the survey, we asked HR managers for permission for data collection. We explained this survey’s objective and interviewed a sample of company HR managers. We gained a team roster from organizations with supportive attitudes to the survey. We allocated a serial code to the respondents to recognize their answers. Of the 179 employees in total, 166 replied, representing a response rate of 92.7%. We collected data by questionnaire survey. The survey items and scales of this research were translated into Korean and received precise validity checks using back-translation by a bilingual Korean–American translator independent of our research team . Our surDemographic characteristics of the respondents consisted of male (70%) and female (30%). The age distribution was as follows: 20s (23.4%), 30s (47.7%), 40s (24.2%), and 50s (4.7%). The average organization tenure was 87 months (s.d.= 84.9). The distribution of rank showed that the majority were junior managers (49.2%), followed by staff (25%), senior managers (17.2%), and directors (8.6%). The average team size was 6.82 (s.d: 2.29), with the smallest team comprising 4 members and the largest team containing 10 members. The table with demographic characteristics is given in All team members, including formal leader, assessed each member’s influence. We provided the team roster to all team members (respondents). The question was “For each person in your team, on the scale from 1 (none) to 5 (very much), please indicate how much influence the person you checked has in the everyday activities of this team” . BecauseWe measured promotive and prohibitive voice behavior rated by the formal leader. To date, most of the previous researchers have focused heavily on both promotion and prevention aspects of voice behavior e.g., ,3,13]. E,13. E3,1We measured the individual perception of LMX using the seven-item LMX-5 Scale . Items aPeer relationship was assessed by team members, excluding the formal leader. We measured indegree centrality in friendship networks among team members using the roster method . Team meWe controlled for organizational characteristics using firm dummy because the three organizations are different in structure and management style. We also controlled for team size because it influences team processes and outcomes. Demographic characteristics were also included in control variables: age, gender, organizational tenure (in months), and rank.p < 0.01) and prohibitive voice  were positively related with individual influence. Also, significant positive correlations were between social relationships and individual influence . b = 0.319, p < 0.001; b = 0.211, p < 0.01). Thus, H1 was supported.We tested the hypotheses using hierarchical regression analysis. b = 0.168, p < 0.05), but the interaction with prohibitive voice was not supported . The interaction effect of promotive voice and LMX on individual influence was plotted in b = 0.420, p < 0.001) and low . Also, as shown in b = −0.464, n.s.; b = −0.302, n.s.). Thus, H3 was not supported.Next, H2 and H3 proposed the moderating effects of LMX and peer relationship. Following Aiken and West (1991), interaction terms were mean-centered in order to reduce multi-collinearity. As shown in 2 = 0.739; prohibitive voice, f2 = 0.592). As shown in model 5 of b = 0.889, p < 0.05) and prohibitive voice .H4 was about the three-way interaction of LMX, peer relationship, and voice. To perform a configurational analysis, we entered the three-way interaction term in the final step . Conversely, b = −1.039, p < 0.05; prohibitive voice: b = −1.215, p < 0.05). As for members with high LMX and low centrality, their voices were unrelated to individual influence . Also, employee voice had a marginally significant relationship with individual influence with low LMX and low centrality . Following Dawson and Richter (2014), we ran the slope difference test )This study makes several theoretical contributions. First, this study can answer the recent calls for investigating the social side of voice consequences. Most voice research has focused on the antecedents of voice, such as psychological safety , disposiSecond, our study contributes to the development of the voice literature from a social relationship perspective. Recent research suggests that not only LMX but also relationships among coworkers impact workplace outcomes ,50. HencMost importantly, our results pave the way for studying, not only the interactions of the relationships with the leader and peers, but also the optimal balance of LMX and peer relationships from the social network perspective. Although previous social exchange research has argued that LMX and TMX are interwoven in a work team , it has In a practical sense, our study suggests that managers can consider voice behavior as an important way of increasing members’ influence in the work team. Along with the recent research emphasizing the voice consequences ,8,71, weMore importantly, this study found that voice and influence relationships are affected by various social relationships. Extant studies have claimed that leaders and coworkers provide benefits for employees who speak up, but sometimes leaders and peers may ignore or reject their colleague’s voice ,10,68. AIn addition, our results imply that LMX is a more critical factor than centrality in friendship networks for employees to gain influence through voice behaviors. Although peer relationships are considered important in the workgroup, their salience may be weaker than that of the vertical relationship between leaders and subordinates. Taken together, this study’s results indicate that managers should consider not only high-quality peer relationships but also sound supervisor-subordinate relationships.Despite its numerous contributions, this study also has several limitations. First, to reduce the common method bias, this study gathered data from two distinct sources: member and leader . HoweverSecond, we tested our research model using data collected from the firms with collectivistic cultures. The unexpected results of this study may be attributable to specific cultural characteristics. Yum (1988) revealed that the main difference between East Asians and North Americans is their emphasis on communication in relation to social relationships. As our data are from Korean companies which emphasize harmonious social relationships, preserving others’ honor based on relational norms is of great importance, rendering straightforward voice behavior less appropriate ,74. ThisAs business environments continue to emphasize flexibility and interdependency in workgroups, the importance of voice behavior cannot be overemphasized. This study investigated the consequences of voice behavior by focusing on voice as a social phenomenon. Overall, from a social relationship perspective on voice behavior, this study revealed the effect of voice behavior on employees’ influence in a team. We also shed new light on the importance of the social relationships within a team—both LMX and peer relationships—by demonstrating how different social relationships separately and jointly affect the voice-influence relationship. This study can be a meaningful step toward discovering voice outcomes from the perspective of social relationships. As employees’ proactivity and change-oriented behavior are required more than ever, managing social relationships within a work team will be a critical task for managers to foster employees’ continuous voice behavior in organizations. This study suggests that designing a work team with high-quality LMX and peer relationships may be an effective means of accomplishing goals. Further studies are needed for a deeper understanding of the consequences of voice behavior.


Humans perceive the external world by integrating information from different modalities, obtained through the sensory organs. However, the aforementioned mechanism is still unclear and has been a subject of widespread interest in the fields of psychology and brain science. A model using two reservoir computing systems, i.e., a type of recurrent neural network trained to mimic each other's output, can detect stimulus patterns that repeatedly appear in a time series signal. We applied this model for identifying specific patterns that co-occur between information from different modalities. The model was self-organized by specific fluctuation patterns that co-occurred between different modalities, and could detect each fluctuation pattern. Additionally, similarly to the case where perception is influenced by synchronous/asynchronous presentation of multimodal stimuli, the model failed to work correctly for signals that did not co-occur with corresponding fluctuation patterns. Recent experimental studies have suggested that direct interaction between different sensory systems is important for multisensory integration, in addition to top-down control from higher brain regions such as the association cortex. Because several patterns of interaction between sensory modules can be incorporated into the employed model, we were able to compare the performance between them; the original version of the employed model incorporated such an interaction as the teaching signals for learning. The performance of the original and alternative models was evaluated, and the original model was found to perform the best. Thus, we demonstrated that feedback of the outputs of appropriately learned sensory modules performed the best when compared to the other examined patterns of interaction. The proposed model incorporated information encoded by the dynamic state of the neural population and the interactions between different sensory modules, both of which were based on recent experimental observations; this allowed us to study the influence of the temporal relationship and frequency of occurrence of multisensory signals on sensory integration, as well as the nature of interaction between different sensory signals. The brain uses numerous sensory inputs to recognize the external world and acquire knowledge. In addition, handling multiple pieces of information in an integrated manner increases the reliability of perceiving the external world and knowledge acquisition. Researchers have investigated this phenomenon, termed sensory integration or multisensory integration, in the fields of psychology, medicine, neuroscience, and artificial intelligence.1. The co-occurrence and combination of specific visual and auditory stimuli exert a significant impact on perception3. In neuroscience, most experimental studies employ the experimental design requiring perceptual decision-making to distinguish between multimodal and unimodal sensory effects5. The models based on Bayesian decision theory succeed in explaining the mechanism underlying multisensory integration, especially the mechanism of perceptual enhancement for combinations of multiple sensory stimuli. The models based on the drift–diffusion theory could explain reaction time in perceptual decision-making of multisensory stimuli7. These models are based on the hierarchical structure, namely feedforward structure, in which sensory information is processed in the corresponding unimodal sensory system  and then transferred to association areas (via a single pathway) for integration with other types of sensory information. According to evidence that the view of the feedforward system is not necessarily consistent with the results of perturbation studies, in which a relevant brain region is inactivated, systems for multimodal sensory integration consist of multiple pathways and are more multifaceted than the feedforward view8. Such interaction between sensory modalities and integration of sensory information through these pathways before it reaches the association cortex would allow for faster perception than the conventional feedforward processing. In addition, because responses of single neurons during multisensory integration are heterogenous, it is also suggested that the contribution of population-level dynamics to the mechanism should be considered8. From the perspective of computer science, one made attempts to model a visual system based on the convolutional neural network (CNN)9 and the mechanism for sound source localization10. Regarding audio-visual integration, the model with self-supervised learning, CNN, and Bayesian theory proposed the mechanism that utilizes correspondence and temporal coincidence between features, each of which is extracted from visual or auditory stimuli24.In psychology, the "McGurk effect" describes the perception of a third phoneme when people listen to one phoneme being vocalized while simultaneously seeing another phoneme being vocalized in a video25. In the early stage of multimodal integration, sensory organs or low-level brain regions, such as the retina/primary visual cortex for the visual system or cochlea/primary auditory cortex for the auditory system, need to extract useful information from such a continuous signal and to encode extracted information as a dynamical state of neural activity. Most of the studies concerning multisensory integration have focused on how to utilize acquired information, i.e., the features obtained after processing the continuous signals, but not on how to extract information from continuous signals27. In addition, the encoded sensory information is assumed to be represented by steady firing rates of a neural population , not by a dynamical state of them. Indeed, the time-varying activity of a neural population has been observed in various brain regions and showed its relevance to brain functions28. Perception of multisensory stimuli depends on the timings of stimuli such as stimuli presented with a certain delay3. This dependence of multisensory integration on the timings could be achieved only with the model based on the dynamical state. Furthermore, because the process is carried out in an unsupervised manner, it is likely that frequent simultaneous presentation of signals from different sensory modes should serve as the cue. Although how multimodal information is constructed from continuous signals has been studied22 from the perspective of machine learning, most of the studies utilize a steady state of the neural population, rather than a dynamical state, as the encoding relies on an artificially layered structure that is not seen in the brain24.Sensory information comprises an uninterrupted time series, and sensory organs transmit it as a continuous signal to downstream areas. Sensory neurons during such a sensory stimulus presentation exhibit dynamic firing patterns, but not steady firing intensities29. The model is based on reservoir computing (RC) because RC is a recurrent network model that handles time series data31. While most models for chunking focus on the transition probability between elements that make up a chunk35, the model utilizes trajectories of states of the neural network responding to sequential inputs. Because sensory signals are not always comprised of separable elements such as letters in a string, the model is more likely to provide a plausible mechanism. Furthermore, because the neuronal network in sensory organs, such as the retina for the visual system, rarely shows experience-dependent plasticity, RC in which recurrent connections are fixed is structurally closer to the system engaging in sensory processing than other types of recurrent neural networks in which all connections are supposed to be modified for learning. Similarly, a reservoir computing model based on predictive coding (PCRC) was proposed36. The PCRC model was constructed such that the sensory information of each modality was supposed to be encoded as predicted information, namely, the encoding neural activity is supposed to reproduce the input. Therefore, in the model, each sensory input is essentially unaffected by the other types of sensory signals, and interaction between different sensory modalities was not considered. On the other hand, the proposed model enables us to consider the effect of direct interactions between sensory modules, which has been suggested by several studies39. In this study, we intended to apply the previously proposed model29 to realize information integration between different modalities through the segmentation of specific stimuli co-occurrence in repeatedly presented time series data and to encode it as a dynamical state.In this study, we aimed to propose a potent model for understanding the mechanism of multisensory integration in the early stage implemented by the brain based on the previously proposed model for chunking29. In the brain, there are different systems, each of which is responsible for the processing of a specific sensory signal, such as signals from the visual system or the auditory system. Therefore, in the model used in this study, two RC networks, each of which is later referred to as an RC module, interacted with each other by feeding their output to the other module for learning. As described below, the model received different modal inputs (images and text tones) to be integrated, each of which is processed by an RC module that corresponds to a sensory system. Each RC module consisted of rate-based neurons in a recurrent network and linear readout units in the output layer. An RC module received the time-varying inputs of a modality, which differed among the modules . The teaching signals are defined by the following equations.We demonstrated the mechanism by which the model learned multiple chunks. The input was made by alternating input sequence and a chunk that was randomly chosen with the same probability among the three. Fig. A, left. We trained the model by using input sequences in which three chunks appeared randomly and consecutively with equal probability Fig. A, right.Next, we investigated the mechanism by which activities of reservoir neurons encoded chunks. We trained the network on sequences containing three chunks and random sequences Fig. A left. EFollowing learning, the norm of ler Fig. A1 and A2N. During each chunk presentation, the activity of the RC internal nodes drew a specific trajectory in the PC1 to PC3 space  of reservoir neurons and the strength (g) of recurrent connections among reservoir neurons  and the integrated output from the model. The missing input signal replaced one of the signals in a chunk pair with another signal or a random sequence, with a probability m  was by the interaction of feedback from the outputs of appropriately learned sensory modules with alignment between sensory modules, suggesting that anatomical connectivity facilitates such an interaction between different sensory systems.i-th readout in either RC module, the teaching signal is supposed to reinforce the i-th readout in the partner RC module by adjusting reservoir-readout connections. Thus, the input will be encoded by the i-th readouts of both RC modules. Considering that the brain possesses sensory module such as visual and auditory cortices and the modules directly interact each other, the interaction between RC modules might be the key for understanding the brain mechanism of multisensory integration. The earliest region where different sensory information converges is the superior colliculus (SC)46. Input from the association cortex assists the SC neurons in learning how to respond to multisensory inputs. In the proposed model, neurons in the association layer correspond to SC neurons, and connections between readout and association neurons should be regulated by the association cortex. However, the proposed model could not incorporate such learning because the association neurons are simplified and the higher layer was not included. In the computational model of multisensory integration based on such anatomical connectivity48, the unisensory modules that send sensory signals to SC neurons are designed to compete with each other in a winner-take-all fashion during the learning phase; this corresponds with the teaching signals employed in the proposed model.Given that an input activates the 36. In the model with a similar structure to the present model, each sensory signal is encoded by the corresponding sensory RC such that the error between a sensory input and the RC output is minimized. Then, a multisensory signal is encoded by combining visual and auditory sensory information processed by the sensory RCs at the upper layer. Because the PCRC model uses predictive coding for encoding50, each sensory RC is trained such that it can generate the output that is the same as the given sensory input. Therefore, a sensory signal of a modality is essentially processed within the corresponding sensory module, while the proposed models interact with the other sensory module.  If direct interaction between sensory modalities is to be considered, it may be necessary to redefine the essential mechanism; for example, what an RC module predicts is the input of a single modality or integrated inputs of related sensory modalities. On the other hand, the interaction between modalities is incorporated in the proposed model, although it is designed as the teaching signal. Furthermore, the model can be transformed as shown in Fig. The PCRC model has been proposed as a model to process time-varying sensory signals and encode them as the dynamical states of neural activity51. Perception by multimodal integration decreased as the delay became longer. The percentage of correct perception drops to 50% when the delay increases to 200–300 ms3. Although the accuracy shown in Fig. 3. Furthermore, such perception highly depends on stimulus types , suggesting that a higher cortical area may be involved in the process. This property would be difficult to reproduce within the present model because the top-down control that would arise from such a higher structure is not represented in the present model.The co-occurrence of stimuli of different modes would be attributable to an identical cause, particularly in the case of frequent presentation. The proposed model was capable of integrating simultaneously presented paired stimuli, and its performance deteriorates with decreased probability of co-occurrence or an increased delay of the presentation of one of the paired stimuli Fig. . Concern3 and “ventriloquism effect”52; the “McGurk effect” is a phenomenon in which an unfamiliar combination of sensory information, each of which is familiar, leads to the new perception, and “ventriloquism effect” is the auditory illusion that sound is perceived as coming from the different location, but not from the location where the sound is actually generated owing to visual stimuli. Both are major issues in multisensory integration because the dependence of perception on temporal aspects of the stimuli would imply that the integration process depends on dynamic shifts in properties of neural activity; the chunking mechanism based on neural population dynamics may also be involved in the illusional perception. The “McGurk effect” can be resolved by treating the multimodal information as a static representation of a joint probability distribution representing combined stimuli of different modalities54; however, it is impossible to treat the “ventriloquism effect” by such representation because it does not incorporate the time course of sensory signals. In particular, it is reported that the “ventriloquism effect” is affected by the temporal difference between visual and auditory stimuli and the symmetrical/asymmetrical effect between visual and auditory stimuli exits52. The present model would enable us to consider the effect of the temporal difference or how to interact between the modules. In the ventriloquism effect, when there is a mismatch between the location of auditory and visual stimuli, a calibration occurs in which the perception of the location of auditory stimulus is drawn to the location of visual presentation. Traditionally, it has been assumed that repeated experience of such mismatch stimuli is required for this calibration to be achieved, but one study found it to occur after only the immediately preceding trial55. Extensions of this model that can encode stimulus location may allow us to test whether such short-term calibration can occur via a bottom-up mechanism, such as memory retention by recurrent dynamics. Therefore, the proposed model may contribute to a unified understanding of how temporal characteristics affect multisensory integration efforts beyond the McGurk and ventriloquism effects.The probability of co-occurrence of paired stimuli and the temporal delay between these stimuli displayed a strong association with the “McGurk effect”2. In our model, the interaction between the different modal modules (RC1 and RC2) was direct. The interaction via a higher layer may be possible because perception requires top-down control from higher-order brain areas, such as the association cortices, whereas direct connections between primary sensory areas allow those areas to interact with each other. In the ventriloquism effect, the influence of visual information on auditory information could be stronger than vice-versa, although either is influenced by the accuracy of modal information.57. It is important to determine whether the above-mentioned asymmetric result is caused by the characteristics of bottom-up processing , by an asymmetric interaction between different sensory modules, or by asymmetric top-down control61.In the proposed model, neurons in the higher association layer were modelled to encode the results of multimodal integration by responding to specific co-occurrences of paired stimuli. This layer should be modelled to integrate multimodal information from the lower layers in a self-organizing manner, which would enable each neuron in this layer to display its response to specific combinations of multisensory information among numerous combinations. This modified version could be tested as a possible underlying mechanism of the “McGurk effect.” For example, the model could be validated by evidence showing that the degree of the “McGurk effect” depends on the temporal order and intervals of auditory and visual stimuli62, each of which has three layers: the input, reservoir, and output. The reservoir layer is a recurrent neural network that consists of N rate-based neurons. A neuron in the reservoir layer obeys the following dynamics:i(t) is the activity of the neuron in the input layer, g is the parameter that scales connections between neurons in the reservoir layer and controls the complexity of the network behavior; the reservoir network shows chaotic spontaneous activity for g > 1. W, Win, and Wback are connections within reservoir neurons, those from the input to the reservoir layer, and those from the reservoir to output layers, respectively. r(t) and Wout are the output of the reservoir neurons, and connection matrix from the reservoir neurons to output neurons that is also called the readout weight matrix, respectively. Each output neuron receives inputs from S reservoir neurons by the weights Wout. The output neurons projected back to all reservoir neurons. Learning was conducted by modifying the readout weight matrix Wout based on the FORCE algorithm that minimizes the error between the output and the teaching signal40. The elements of W are generated by a Gaussian distribution of N) where p is the probability of connections between reservoir neurons. The elements of Win were determined such that each row had only one non-zero element generated by a normal distribution N. Elements of Wback were drawn from a uniform distribution . The initial values of Wout are generated by a Gaussian distribution N. Table 63.In this study, we adopted a collaborative RC model that was originally developed to extract meaningful segments from information streams. The model consisted of two recurrent networks called echo state networks (ESNs)mentclass2pt{minimT = 15,000 ms.In the learning rule, we normalized the outputs such that the mean and the standard deviation of outputs were satisfied with 0 and unity, respectively:i-th normalized output. The threshold linear function [x]+ returns 0 for x ≤ 0 and x for x > 0; therefore, the output value was positive. The numerator inside the function tanh takes a positive value if the i-th readout showed the largest response because the second term of the numerator represents an average except the i-th readout. Therefore, when the i-th readout of an RC module responded to a chunk the most, the teacher signal reinforces the i-th readout of the other RC module. Each output neuron in an RC module received the teacher signal defined by Eq.  for the final performance comparison of the model. We set the constants to δ = 0.5.From the symmetry of the teacher signals for RC1 and RC2, i-the readout in the RC1 is responsible for the chunk “apple”, while the j-th readout in the RC2 may respond to the chunk “apple”. The neurons in the association layer must organize the outputs of RC1 and RC2 so that each neuron in the layer represents one of the learned chunks. For this purpose, we introduced the learning rule into connections from the readouts of RC1 and RC2. Let j-th readout of RCx to the i-th neuron in the association layer. The output of oi(t) and the dynamics N is the number of readouts or neurons in the association layer (N = 3). The first and second term of the right-hand side represents the Hebbian rule and the normalization, respectively.In the alternative models presented in Fig. o(t) be the output to be analyzed. Convolution of o(t) with the window function w(t): Let C represents the total number of stimulus presentation epochs, including random sequences . cij represents the element in the i-th row and the j-th column. Therefore, the numerator is the sum of diagonal elements, indicating the sum of correct responses for all presentations. Considering learning was unsupervised, the stimulus selectivity was not explicitly imposed on each unit. Therefore, we determined the assignment of chunk selectivity for each unit such that the accuracy could be maximized.According to the obtained confusion matrix, the accuracy rate was calculated as follows:To define the response selectivity of reservoir neurons, we sorted them based on their mean activation phases:t when an input X is presented for the i-th trial is denoted by t averaged over trials, which is denoted as the center point at t for input X, is obtained as And nX is the number of trials for input X.A state of an RC module in low-dimensional space spanning from PC1 to PC3 at t is defined as Thus, the distance between the center points of input X and Y, t = 0. Therefore, we decided to characterize it by cutting out the 100 steps before and after t = 0 and integrating the time points.Therefore, we defined the degree of separation between trajectories of input X and Y as The smaller the value of 44. For example, in the effective dimension, if n principal components equally share the total variance and the remaining N principal components have zero variance, then Effective dimension is a measure of the effective number of principal components describing a trajectoryThe effective dimension is given bySupplementary Information.


We conclude that AE-AE is an effective and safe technique for the treatment of acquired stage Ib and II cholesteatoma present in the attic and tympanic cavities.This study aims to test the effectiveness and safety of exteriorization surgery comprising atticotomy and obliteration of the additus ad antrum, also referred to as attic exposition–antrum exclusion (AE-AE) surgery. This surgery combines otoendoscopy with surgical microscopy for the treatment of acquired pars flaccida cholesteatoma in stages Ib and II  present in the attic and the tympanic cavity. We reviewed a historical cohort of 65 patients. Of the total, 21 were treated with canal wall-up tympanomastoidectomy (CWU). Patients in whom the AE-AE technique was performed had residual and recurrence rates of 0% and 9.1%, respectively, compared with 28.6% and 9.5%, respectively, for those treated with CWU. In the AE-AE procedure, surgery is performed in one stage compared with the two stages in CWU, to address the risk of residual cholesteatoma. Auditory thresholds were higher in the CWU group compared with the AE-AE group in the pre-surgery (53 ± 16 vs. 44 ± 15 dB;  Middle-ear cholesteatoma is characterized by the existence of epithelial tissue with aggressive and destructive behavior in the tympanic and mastoid cavities . AlthougAE-AE is technically and conceptually characterized by the complete exposure of the attic by reaming the upper wall of the external auditory canal , which allows the exclusion of the antrum and mastoid via closure of the additus through cartilaginous grafts. Using the classification of the IOOG, the categorization of this technique corresponds to an atticotomy with partial obliteration of the additus . The attFinally, we find that the use of otoendoscopy in this technique reduces recurrence due to persistent cholesteatoma, mainly in the epitympanum and mastoid antrum. The introduction of an endoscope is also significant in ossicular reconstruction.The objective of this study is to estimate the effectiveness and safety of AE-AE with endoscopic support when used to treat cholesteatoma occupying the attic and tympanic cavity in stages Ib and II according to the classification of the Japan Otological Society  Table 1.Using a historical cohort design, 65 patients undergoing their first surgeries between 2001 and 2020 with a diagnosis of stage Ib or II acquired attic and tympanic cholesteatoma were included [This research was approved by the Ethics Committee (2020/86). All patients were operated on with either (a) the AE-AE technique with the use of an otoendoscope or (b) the canal wall-up tympanomastoidectomy technique with only a microscope. The stage of cholesteatoma was established from the operative findings recorded in the clinical history as well as by reviewing the extent described in the surgical protocol and confirming the histopathological diagnosis of the pathological anatomy.All patients underwent preoperative computed axial tomography and surgery with intraoperative facial nerve monitoring according to a previously published protocol . AudiomeWe determined the difference between the AC and BC PTAs (ABG) pre- and post-surgery and determined whether the values were less than 20 dB, which was used as the criterion for a good post-surgical hearing outcome. When necessary, patients underwent an ossiculoplasty procedure in the same surgical act as cholesteatoma exeresis, using either pinna or tragus cartilage over the stapes or total or partial titanium prosthesis. Treatment of the tympanic membrane was performed with temporalis muscle fascia or tragus perichondrium.The inclusion criteria were as follows: attic cholesteatoma of stage Ib or II affecting only the attic or both the attic and the tympanic cavity; first intervention on the pathological ear; and patients undergoing AE-AE with the use of a microscope and an otoendoscope or undergoing CWU with only the use of a microscope. The exclusion criteria were the absence of cholesteatoma during surgery, cholesteatoma not acquired from pars flaccida, and prior surgery in the affected ear. Age, sex, affected ear, residual disease, and time of recurrence (if any) were also recorded in the clinical history.Five surgeons with more than 10 years of experience in otologic surgery operated on the patients using the CWU technique. These surgeons were not exclusively dedicated to the treatment of ear pathologies but were specialists in otolaryngology and general cervical pathology. The series of patients who underwent CWU were operated on between 2001 and 2013, a period prior to the creation of super-specialty units in our hospital. The otology unit currently has 2 surgeons who have performed all surgeries with microscopes and endoscopes since 2013. We performed AE-AE hybrid surgeries using standard microsurgical and otoendoscopy instruments.The following is a description of the surgical steps, which are based on the IOOG categorization . Retroauricular approach (A4);Tympanomeatal flap is lifted, and the middle ear is explored;Excision of middle-ear cholesteatoma and exploration of ossicular chain and incudostapedial articulation;Mastoidectomy with canal wall preserved and posterior tympanotomy M1b with additional combination of M1b and M2a (atticotomy);No external ear canal reconstruction (Ex);No obliteration (Ox);No bone removal from external ear canal wall (Ax);Tympano-ossicular reconstruction if necessary .CWU reconstruction technique:All cases were scheduled for second-look (S2p) revision between 1 and 2 years. Surgeons did not use otoendoscopes or diffusion MRI to assess residual disease.AE-AE hybrid exteriorization technique is shown in Following the steps previously described by other authors ,7,8, we 9.Retroauricular approach (A4);10.Tympanomeatal flap is lifted, and middle ear is explored;11.Excision of middle-ear cholesteatoma and exploration of ossicular chain and incudostapedial articulation using endoscope and microscope;12.Atticotomy (M2a). Superior wall of EAC is drilled with two hands and microscopic control, exposing entire tegmen tympani. Once attic is completely exposed , cholest13.No external ear canal reconstruction (Ex);14.Partial obliteration of additus (O1) using cartilage. Once cholesteatoma is removed, we proceed to closure of additus and, therefore, antroexclusion using several pieces of cartilage. Here, again, the use of an endoscope allows for perfect antroexclusion.15.No bone removal from external ear canal wall (Ax);16.Tympano-ossicular reconstruction, if necessary , using endoscope and microscope.17.Superior meatoplasty. To favor marsupialization of attic and self-cleaning, we perform an upper meatoplasty by incision at 12 o’clock in upper wall of EAC and removal of cartilaginous tissues. Place tamponade with gauze edge soaked in antibiotic and corticosteroid creams and remove after 10 days.Using endoscopes in different stages allowed us to access areas of the middle ear for which visualization was very difficult, allowing cholesteatoma elimination and epithelium cleaning, mainly in the epitympanum and tympanic sinus in addition to the hypotympanum, protympanum, and supratubaric fossa.This study is observational in nature, involving a comparison of the surgical performances of otologists (2 surgeons) and general ENT specialists (5 surgeons) during different periods of time. Although the patients were not randomized, the fact that the recurrence rates are similar to those reported in other studies leads us to conclude that the surgeon is not a factor influencing the recurrence rate. We do not know if the results would change (better outcomes) if the otologists had performed the CWU procedures, although we consider super-specialization to be important in ENT surgeries.Categorical variables are expressed as frequencies and percentages. Quantitative variables are expressed as means and standard deviations. The proportions between surgical groups for sex, affected ear, stage of cholesteatoma, facial nerve dehiscence, reconstruction, recurrence, and PTA were compared using chi-squared tests or Fisher’s exact tests, when appropriate. Comparisons between surgical groups for age, time to recurrence, and audiometry were carried out using Mann–Whitney tests. The determination of the pre–post-surgery period within each surgical group was carried out with Friedman or Wilcoxon tests, as appropriate. p-values below 0.05 were considered to indicate statistically significant differences. Statistical analysis was performed using SPSS  and LogXact-4 for Windows .All p = 0.005.Sixty-five patients were included in the analysis. They were divided into two groups according to whether the surgical technique used was AE-AE with endoscopes or CWU. The distribution and demographic variables are shown in p = 0.04.Regardless of the type of surgery, the residual disease and recurrence rates were higher in patients with stage II cholesteatoma  than in those with stage Ib cholesteatoma , with The residual disease, but not recurrence, rate was lower for patients in whom the AE-AE technique was performed compared with those treated using CWU see : 28.6% aIn the CWU group, 6 (28.6%) patients had an affected sinus tympani due to previous surgery compared with 8 (18.2%) patients in the AE-AE group. In both groups, no recurrence was found for previously affected sinus tympanicum ears. All cases of recurrence in the CWU group were due to failure in attic reconstruction, whereas failure in the AE-AE group was due to an error in the obliteration of the additus ad antrum. n = 26 (59.1%)) and in the CWU group (n = 11 (52.4%)). No difference was found in surgery time between the stage Ib group (158 ± 58 min) and the stage II group (181 ± 51 min), with p = 0.17. No differences were observed in the neurophysiological dehiscence of the facial tympanic portions.The most frequent reconstruction technique for the chain was cartilage over stapes, both in the AE-AE group (p = 0.039) but not at one or more years post-surgery  or in pre–post-surgery comparisons, either within the AE-AE technique (p = 0.89) or within the CWU technique (p = 0.96). Overall, no differences in PTA were found between both groups (p = 0.49) or when comparing the hearing levels of partial reconstruction with cartilage over stapes  greater than 20 Db post-surgery in four patients from the CWU group and one patient from the AE-AE group. All of these patients had previous high-frequency affectations prior to surgery. The main objective of surgical treatment for cholesteatoma is removal with a minimum rate of recurrence. Canal wall-up and canal wall-down techniques have classically been performed depending on multiple factors. For stage Ib or II cholesteatoma of the attic and tympanic cavity, we modified an AE-AE technique performed in the 1980s ,6,7,8 inWe provide evidence here for lower residual and recurrence rates in acquired stage Ib and II cholesteatoma of the attic and tympanic cavity when using the AE-AE 0–9.1%) technique in combination with otoendoscopy in comparison with the CWU technique 28.6–9.5%). When we contrast our results with those of other authors, we can see that the CWU technique has residual and recurrence rates between 17 and 61% .1% techn reported.6–9.5%. The impression that the residual rate in the CWU group is high is due to a number of factors. Mainly, exposure of the attic, antrum, facial recess, and sinus timpani is more limited following the CWU procedure, which may lead to difficulty in the complete removal of all involved air cell tracts and in the elimination of cholesteatoma during the initial procedure . Due to Second, the epitympanum and mastoid cavity are ultimately relined with nitrogen-absorbing cuboidal mucosal epithelium after the CWU procedure, and the presence of this mucosa can result in the development of continued mucosal inflammation and recurrence . We conclude that there are several factors contributing to the decrease in the recurrence rate for the AE-AE procedure. As described in other articles ,8,11, a In contrast to other authors , we moniSimilarly to other authors ,16,17, wAs with other research , the attFurthermore, in other research , the surIn the group of patients treated with AE-AE using otoendoscopes, the most frequent treatment of the chain was partial reconstruction with cartilage on the stapes superstructure. We preferred autologous material to other types of materials, as we find, in line with other authors, that it provides functional benefits and allows us to reinforce the tympanic membrane, achieving acceptable functional results with post-surgical thresholds of 41 dB and a residual ABG of less than 20 dB, consistent with other studies .In 18.2% of the patients, we performed total reconstruction with titanium prostheses, obtaining thresholds of 46 dB and a residual ABG of less than 20 dB in 28.6% of the patients. We found no statistically significant differences between partial reconstruction with cartilage over stapes and total reconstruction with titanium prosthesis when studying ABG, which is consistent with the literature [There are reports  of high-The AE-AE procedure utilizing an endoscope is a safe technique that significantly reduces the rates of cholesteatoma persistence and recurrence and shows good auditive results. It allows patients to have excellent quality of life, normalized bathing, and a reduction in surgical revisions when used in the treatment of attic acquired cholesteatoma. There is a need for controlled clinical trials to demonstrate the benefits of the AE-AE method compared with other techniques.


A COVID-19 vaccine booster dose is effective and safe for older adults. This study investigated facilitators and barriers to take up a COVID-19 vaccine booster dose among older adults in Hong Kong. Participants were Chinese-speaking community-dwelling adults aged ≥65 years. Telephone numbers were randomly selected from up-to-date telephone directories. A total of 395 participants completed the telephone interview. Logistic regression models were fitted. Among the participants, 31.6% received a COVID-19 vaccine booster dose. After adjustment for significant background characteristics, positive attitudes toward the booster dose, perceiving significant others would support them to receive the booster dose, and less uncertainty regarding the choice of the booster dose was associated with higher uptake of a COVID-19 vaccine booster dose. Concerns about poorer responses to the booster dose due to older age and the presence of chronic conditions were negatively associated with the dependent variable. In addition, the belief that governmental promotional materials could address their concern and were helpful for them to make decisions was associated with a higher COVID-19 vaccine booster dose uptake. Improving booster dose health promotion materials, modifying perceptions, involving significant others and reducing uncertainty are potentially useful strategies to improve COVID-19 vaccine booster dose uptake among older adults. The cru = 8787) . The maj = 8787) .COVID-19 vaccination is effective and safe for preventing severe consequences and deaths caused by COVID-19 among older adults . HoweverPeople may be hesitant to receive a COVID-19 vaccine booster dose. At least eleven studies investigated willingness to receive a COVID-19 booster dose ,29,30,31Across countries, history of seasonal influenza vaccination, perceived higher risk and severe consequences of COVID-19, belief in vaccine efficacy, and trust in information obtained from social media and significant others were found to be facilitators to receive primary COVID-19 vaccine series among older adults ,43,44,45This study investigated facilitators and barriers to receive a COVID-19 vaccine booster dose among a random sample of community-dwelling persons aged 65 years or above in Hong Kong. We hypothesized that older people who had supportive perceptions of the booster dose, with less uncertainty when choosing a booster dose, and a higher level of satisfaction with governmental booster dose promotion materials would have higher uptake of COVID-19 vaccine booster dose.n = 56,827) on 2 March 2022. By the end of this study (13 April 2022), daily confirmed cases dropped to 1043. We present the COVID-19 situation in Hong Kong during the study period in A random telephone survey was conducted among community-dwelling Chinese-speaking individuals aged ≥65 years in Hong Kong from 14 February to 13 April 2022. During the study period, Hong Kong was experiencing the fifth wave of COVID-19 outbreak caused by the Omicron BA.2. The number of daily confirmed COVID-19 cases was 1619 on 14 February 2022, and this peaked (The inclusion criteria were: (1) community-dwelling Chinese-speaking individuals aged ≥65 years, and (2) having a Hong Kong ID card. We excluded those who were not able to communicate effectively with the study interviewers.Our target sample size was 400. We assumed the uptake rate of the COVID-19 vaccine booster dose to be 50%. Assuming the uptake rate in the reference group (without a facilitating condition) to be 10–40%, the sample size could detect the smallest odds ratio of 1.76 between people with and without a facilitating condition . According to the Hong Kong census data in 2021, 18.2% of Hong Kong residents were 65 years or above . AssuminThe research team input all household telephone numbers listed in the most up-to-date telephone directories about 350,000) into an Excel file and randomly selected 4000 household telephone numbers by using the function of “select random cells”. Trained interviewers conducted the telephone calls during 6–10 p.m. on weekdays and 2–9 p.m. on Saturdays to avoid under-sampling of working individuals. If the initial call was not answered, four more follow-up calls were made during different time slots before we considered the household to be non-valid (one without an eligible participant). In case there was more than one person in the household who was aged ≥ 65 years, the interviewers invited the one whose last birthday was the closest to the interview date to complete the survey. This was to avoid data contamination and the introduction of extra confounding factors. After screening the eligibility, interviewers briefed prospective eligible participants about the study, and made guarantees of anonymity, the right to quit at any time, and that refusal would have no consequences. Since there was no face-to-face contact and the study was anonymous, we obtained verbal informed consent from the participants. The interviewers signed a form pledging that the participants had been fully informed about the study. The same procedures have been used in previous random telephone surveys targeting local older adults ,49,50. T,000 intoWe performed in-depth interviews to understand older adults’ perspectives of a COVID-19 vaccine booster dose. Five community-dwelling Chinese-speaking individuals aged ≥ 65 years were recruited through purposive sampling . Prior to the interview, fieldworkers explained the purposes and nature of the interviews. With verbal informed consent, interviews were conducted through telephone and audio recorded with informants’ consent. The interviews lasted for about one hour. We transcribed interviews and kept a code book to record special data and transform the data into categories to identify main themes. Three out of five informants intended to receive a COVID-19 vaccine booster dose in the future. We identified three themes related to facilitators: (1) concern that the protection conferred by the primary vaccine series would decline over time, (2) belief that a booster dose could reduce the risk of having Omicron BA.2 and the risk of death, and (3) suggestions from the government, doctor, and family members to receive a COVID-19 vaccine booster dose. Four other themes were related to barriers. They were: (1) not knowing which type of vaccine was better for them as a booster dose, (2) belief that older people would respond less well to a booster dose (less effective and more side effects), (3) concern about potential interactions between chronic diseases and a booster dose, and (4) concern about the duration of protection of a booster dose. Based on the qualitative findings, a panel of researchers in public health, behavioral health, and vaccination behaviors developed the questionnaire. The questionnaire was tested among 10 older adults to assess clarity and readability. All older adults participating in the pilot study believed that the questions were understandable and the length was acceptable. These older adults did not participate in the actual survey. The panel finalized the questionnaire based on the pilot testing results.Participants reported sociodemographic characteristics, the presence of chronic conditions, history of COVID-19, and history of seasonal influenza vaccination and pneumococcal vaccination.Participants reported the number of doses and types of COVID-19 vaccines received as primary vaccine series and the booster dose. Participants who had received a booster dose were asked for some details, such as the severity of side effects of the booster dose and whether such side effects were milder or more severe than the primary vaccine series.We adapted the 3-item scale measuring positive attitudes toward a COVID-19 vaccine booster dose validated in the Chinese population . One iteWe used the questions validated in Hong Kong older adults to assess satisfaction with COVID-19 vaccine booster dose health promotional materials produced by the Hong Kong government . The quep < 0.05 considered as statistically significant.The frequency distribution of all variables was presented. Mean and standard deviation (SD) of the items and scales representing perceptions related to the COVID-19 vaccine booster dose were also presented. Cronbach’s alphas were calculated by using reliability tests. We used principal component analysis with varimax rotation to perform exploratory factor analysis. The dependent variable was self-reported uptake of a COVID-19 vaccine booster dose. Univariate logistic regression models first assessed the significance of associations between background characteristics and the dependent variable. We then fitted a single logistic regression model involving all significant background characteristics and one independent variable of interest. A summary multiple logistic regression model was fitted considering all significant variables in univariate analysis. Crude odds ratios (OR), adjusted odds ratios (AOR), and their 95% confidence interval (CI) were obtained. In addition, correlations between perceptions and satisfaction with the health promotional materials were investigated. SPSS 26.0  was used for data analysis, with About half of the participants were 65–69 years (49.9%) and female (60.3%). The majority of them were married or cohabited with a partner (75.4%), did not receive tertiary education (89.9%), without a full-time or part-time work (85.8%), and had a monthly household income below HKD 20,000 (USD 2580) (73.9%). Over 60% of them had at least one chronic condition (60.8%). The most prevalent chronic condition was hypertension (47.6%), followed by diabetes mellitus (19.2%), chronic cardiovascular diseases (10.9%), and chronic lung diseases (10.9%). Among the participants, 10.6% reported a history of COVID-19, and 44.3% reported having an acquaintance with a history of COVID-19. At the survey time, 63.8% had received a seasonal influenza vaccination in their lifetime, and 42.5% received it both in the current and previous seasonal influenza seasons. In addition, 27.6% received pneumococcal vaccination in their lifetime .n = 125) received a COVID-19 vaccine booster dose. More participants chose Comirnaty  rather than CoronaVac  as their booster dose. Twelve participants mixed COVID-19 vaccine booster doses; eleven switched from CoronaVac to Comirnaty, and one switched from ZAD1222 to Comirnaty when receiving the booster dose. Over half of them reported no side effects of the COVID-19 vaccine booster dose, and 88.8% reported such side effects were about the same or even milder than those of their primary series , could effectively protect them from COVID-19 variants of concern (60.0%), and could prevent severe consequences of COVID-19 (82.5%). Relatively few participants were concerned that older age would lead to a lower level of protection (10.9%) and a higher level of side effects of the COVID-19 vaccine booster dose (14.2%). About 70% of them were sure about which type of the COVID-19 booster dose was suitable for them and which type they should choose. About 90% of the participants believed that governmental COVID-19 vaccine booster dose promotional materials were easy to understand (87.8%), 42.3% believed such materials could address their concerns related to the booster dose, and 48.6% perceived such materials as helpful for them when making the decision to receive the booster dose .In univariate analysis, higher education level and history of pneumococcal vaccination was associated with higher uptake of a COVID-19 vaccine booster dose . After aUncertainty Scale remained significantly associated with the dependent variable in the multiple logistic regression model . However, education level, history of pneumococcal vaccination in the lifetime, positive or negative attitudes, perceived subjective norm, or satisfaction with the health promotional materials became statistically non-significant in the multiple logistic regression model .Positive attitudes, perceived subjective norm, perceived behavioral control, and satisfaction with the health promotional materials were associated with less uncertainty, while negative attitudes were associated with higher uncertainty. Positive attitudes, perceived subjective norm, and perceived behavioral control were also associated with higher satisfaction with the health promotional materials, while negative attitudes were associated with lower satisfaction .This is one of the first studies examining facilitators and barriers of COVID-19 vaccine booster dose uptake among older adults in China. During the study period, 91.9% of participants received at least one dose of the COVID-19 vaccine, and 31.6% received a booster dose. Perceived threat of the ongoing outbreak of COVID-19 might motivate many older adults to complete their primary vaccine series and to receive the booster dose, as the proportion of taking up at least one dose of COVID-19 vaccine in this group was much higher than that observed between November 2021 and January 2022 (about 60%) . The uptHigher education level was positively associated with COVID-19 vaccine booster dose uptake among our participants. Such a finding was similar to those of previous studies, as higher education level was associated with a higher completion rate of primary COVID-19 vaccine series among older adults in Hong Kong  and highThis study provided some practical implications to increase coverage of the COVID-19 vaccine booster dose among older adults in Hong Kong. First, it is necessary to improve the existing COVID-19 vaccine booster dose promotional materials in Hong Kong. The information on these materials was friendly to older people, as about 90% of the participants found it easy to understand. However, about half of the participants thought such materials could not address their greatest concern related to the COVID-19 vaccine booster dose. A similar proportion of participants believed such materials were not helpful for them when it came to deciding to receive the booster dose. Since the satisfaction with the health promotional materials was a facilitator to receive the booster dose, it was important to improve the contents. Our studies revealed some concerns specific to older adults in Hong Kong. About 10–20% of the older adults in our study had concerns about interactions between old age, chronic conditions, and COVID-19 vaccine booster dose, such as whether older age and the presence of chronic conditions would result in poorer responses to COVID-19 vaccine booster dose . Local evidence showed that the protection against severe/fatal diseases and death conferred by the Comirnaty and CoronaVac was similar in older adults and their younger counterparts . MoreoveAlthough this study was based on a random and population-based sample, it had several limitations. First, compared to census data , people Community-dwelling older adults aged 65 years or above in Hong Kong reported a lower uptake of COVID-19 vaccine booster dose than their younger counterparts. Existing COVID-19 booster dose health promotional materials might not adequately address older adults’ main concerns. Such materials could be improved by addressing concerns about how older age and the presence of chronic conditions would affect responses to the COVID-19 vaccine booster dose. Strengthening positive attitudes, involving significant others of older adults, and reducing uncertainty about the choice of the booster dose might be useful strategies to increase the uptake of COVID-19 vaccine booster dose in this age group.


The reluctance of individuals to obtain solid vaccine-induced immunity represents a fundamental challenge to containing the spread of SARS-CoV-2, including its highly mutated variants. We aimed to assess vaccination acceptance and associated factors for the COVID-19 vaccine booster dose among elderly people (≥60 years old) in China, providing a theoretical and practical reference for universal vaccination policy.Via a backward stepwise method, multivariable logistic regression models were established to assess factors associated with booster dose acceptance. Two-sided P < 0.05 was considered statistically significant.A national anonymous survey was conducted in mainland China from May 25 to June 8, 2022, using a stratified random sampling method. Individuals 60 years of age and above were the target population. A chi-squared test and Cochran-Armitage test for trend were used to compare and examine vaccine acceptance rates by characteristics. Of 3,321 eligible participants, 82.8% (95% CI: 81.5–84.1%) were willing to receive COVID-19 vaccine booster shots. Concerns about contraindications (38.3%), vaccine safety (32.0%), and limited movement (28.0%) were the main reasons for vaccine hesitancy. Nearly one-third still believed that the booster dose was unnecessary after receiving the initial vaccination. Older adults with a low level of perceived barriers , a high level of perceived benefit , and higher cues to action  were more likely to accept the booster dose. Other major factors affecting the booster dose acceptance rate were occupation, time spent on social media, vaccination history, and a high knowledge score for COVID-19 and vaccines. In addition, for those over 70 years of age, rising awareness of susceptibility could be a better gateway for improving their willingness to get vaccinated.A total of 82.8% of recruited older adults were willing to receive the booster dose. Acceptance behaviors were closely related to occupation, time spent on social media, vaccination history, knowledge factors, perception of barriers, and benefit, as well as action cues. Targeted public health measures are a priority for improving the vaccination coverage of valid immunity among the elderly population, not only to prevent infection and poor prognosis caused by emerging variants but also to reduce the huge disease and economic burden caused by the long-term sequelae after SARS-CoV-2 infection. Withter dose . Moreoveter dose .The reluctance of people to obtain solid vaccine-induced immunity represents a fundamental challenge to containing the spread of SARS-CoV-2 , 13. AccThe entire medical community has invested enormous efforts in developing and delivering COVID-19 vaccines, and vaccination campaigns among adults are in full swing, such as in China. The Chinese government has continued to encourage older people to get vaccinated, especially for booster shots , 34. Comvia an online platform called Wen Juan Xing . Covering at least 2.6 million registered members in China, we could easily reach an authentic, diverse, and representative sample  Chinese citizens; (2) ≥60 years old; (3) people who agreed to participate in this survey; and (4) completed the survey between May 25, 2022 and June 8, 2022. To recruit enough representative respondents, we randomly sampled potentially eligible subjects in 31 provinces according to the proportion of adults aged 60 and above reported in the Seventh National Census  among older people . The reliability of this questionnaire  was confirmed by Cronbach's alpha coefficient by different dimensions . Each question was followed by a reminder that all answers were supposed to reflect the reality and true thoughts of those older adults.The questionnaire was constructed and revised by a panel of experts, including one public health expert and two epidemiologists specializing in infectious diseases . We perfThe primary outcome was the acceptance rate of the COVID-19 vaccine booster, defined as the proportion of participants who answered “yes” when asked whether they were willing to receive the COVID-19 vaccine booster dose if available. If a respondent had any concerns or reluctance, the questionnaire would automatically jump to the specific reasons for hesitation.Sociodemographic characteristics and health status of the sample population were investigated, including region, age, sex, marital status, education level, occupation, income, history of chronic disease, and COVID-19 vaccination. The amount of time people spent checking the news about COVID-19 or vaccines on social media each day and people's satisfaction with the government's response to COVID-19 were also obtained.For knowledge factors, we set six and four questions to determine the knowledge level of the elderly on COVID-19 and COVID-19 vaccines, respectively. Sources of SARS-CoV-2 infection, common symptoms, transmission routes, high-risk groups, self-protection measures, and herd susceptibility were the investigational scope of the former aspect, with a total of 19 scores. Scores of “0–6,” “7–13,” and “14–19” represented a “low,” “moderate,” and “high” degree, respectively. For the knowledge on COVID-19 vaccines component, we mainly focused on price, time for booster vaccination, immunity induced by vaccines, and adverse reactions after vaccination. Each correct choice received 1 point, and a total of four scores were assigned to this part. Then, all respondents were divided into three groups  from low to high.As one of the most common theories reflecting individual behavior change, the HBM is an organic combination of motivation theory, cognitive theory, and expectancy-value theory, which has been widely used to explain public attitudes toward vaccines and predict people's vaccination behavior –21. ConsP < 0.05 was considered statistically significant.We performed descriptive analyses to summarize the characteristics of the recruited population by frequencies and percentages. The independent Chi-squared test and Cochran-Armitage test for trend were used to compare the differences between groups stratified by the abovementioned characteristics. To identify factors that influence vaccination willingness, multivariable logistic regression analyses were performed in different groups of participants, including three age groups  and those who had not yet received the booster dose. All independent variables were added to our multivariable models, and adjusted odds ratios (aORs) and 95% CIs were calculated via a backward stepwise method (P < 0.2). The Hosmer and Lemeshow test was used to assess the goodness of model fitting. All statistical analyses in this study were conducted using SPSS 26.0  and R 4.1.3 , and two-sided Ptrend < 0.05). Significant differences in vaccine acceptance were not found between groups stratified by region, sex, occupation, and economic condition .A total of 3,321 respondents were eventually included in our analyses , and 1,0P < 0.05) (P > 0.05). Elderly people who believed in the safety and effectiveness of COVID-19 booster shots showed higher acceptance rates of 83.20% (81.90–84.50%) and 83.80% (82.40–85.10%), respectively. Similar results were exhibited for the dimension of the perceived benefit of the COVID-19 booster shot. Based on the analysis of five dimensions of the HBM, the higher the perception of susceptibility, benefit, and cues to action, the higher the vaccination acceptance rate among the elderly .Concerns about the susceptibility of themselves and family members to SARS-CoV-2 infection indicated a higher acceptance rate of the booster dose among the older population ( < 0.05) . On the For all 3,321 participants, our multivariable logistic regression indicated that the main factors related to COVID-19 vaccine booster dose acceptance were occupation, time spent on social media, and higher knowledge scores on COVID-19 and vaccines . VaccinaAmong the 1,554 participants who did not receive booster shots, 65.3% showed a willingness to receive the booster vaccination. A higher level of perceived benefit  and cues to action  indicated a higher willingness to receive a booster dose among those elderly people. Additionally, occupation, time spent on social media, and vaccination history could also affect the attitudes of elderly people toward booster vaccination .Among the 571 (17.2%) participants who were reluctant or refused to receive the booster dose, nearly one-third were still unaware of the importance of booster shots, believing that it was unnecessary to receive a booster dose as they had already received one or two doses of the initial vaccination . A totalAs a high-risk population with poor prognosis after infection, older adults are the key population for follow-up booster vaccination. We found that, of the 3,321 participants recruited, 82.8%  were willing to receive COVID-19 vaccine booster shots. Concerns about contraindications, vaccine safety, and limited movement were the main reasons for vaccine hesitancy. Factors related to vaccine acceptance rate were occupation, time spent on social media, vaccination history, knowledge factors, and perception of barriers and benefit, as well as action cues. For the over 70s, increasing their awareness of susceptibility could be a better gateway for improving vaccination acceptance. Given the current global epidemic situation and the prevalence of highly infectious variants, it is likely that the subsequent second and third booster shots or vaccines against specific variants will soon be administered globally . Older aBased on our study, 82.8% of 3,321 participants recruited were willing to receive COVID-19 vaccine booster shots. As the high-risk group for severe illness and death after SARS-CoV-2 infection, 87.6 million people (33.2%) aged 60 years and above in China have yet to receive booster shots as of August 10, 2022 . To dateP > 0.05). Multiple studies have shown that higher perceived severity is negatively associated with vaccine hesitancy (P < 0.05), which highlighted the importance and advantages of families and healthcare workers encouraging vaccination for eligible older persons. Similar results can also be verified . The patients/participants provided their written informed consent to participate in this study.Conceptualization: CQ, MD, and WY. Methodology and analysis, visualization, and writing—original draft preparation: CQ. Review and editing: LT, WY, MD, QL, and ML. Supervision: JL. All authors have read and agreed to the published version of the manuscript.


Objective: The COVID-19 pandemic is still continuing throughout the world, with newer genetic variants regularly appearing from different parts of the world. Considering the waning of immunity against COVID-19 infection even with two doses of the COVID-19 vaccine, regulatory authorities have authorised booster COVID-19 vaccination in many countries, especially for vulnerable populations, including healthcare workers. The current study analysed factors predicting the third (booster) dose of COVID-19 vaccine intention, including the health belief model (HBM), among the healthcare workers in Saudi Arabia. Methods: The current study was a cross-sectional online survey performed from 1st October 2021 to 30th November 2021, using a questionnaire prepared in GoogleTM form among healthcare workers in Saudi Arabia. The questionnaire asked demographic factors, COVID-19 experience of participants, subjective assessment of health, intention of COVID-19 booster dose vaccination, preferences for local/foreign-made vaccines, and health belief of the study population related to COVID-19 infection and COVID-19 booster dose. Results: This study received 2059 complete responses. The study population reported mixed health belief with respect to the susceptibility of COVID-19 infection, and higher health belief perception regarding the severity. The perceptions of the study participants regarding the benefits of COVID-19 booster dose were positive. There were few barriers to COVID-19 booster dose expressed by study participants. A total of 1464 (71.1%) study participants reported positive intent for receiving a COVID-19 booster dose. The study showed significant association between definite intention to receive a booster dose and nationality (p = 0.001), marital status (p = 0.017), gender (p < 0.001), education level (p = 0.001), monthly income (p < 0.001), and co-morbid medical illness (p = 0.045). The perception of the COVID-19 booster vaccine as a good idea to minimise worries about getting COVID-19 , and perceptions that receiving the third (booster) dose reduces the risk of COVID-19 infection and associated complications , of the perceived benefit construct of HBM, predicted significantly higher definite intention to receive a booster dose. The concern with the safety of the vaccine  under the perceived barriers construct of HBM predicted as significantly higher no definite intention to receive a booster dose. Conclusions: The results of the present study can guide policy makers in their efforts to promote booster doses of COVID-19 vaccination among the healthcare workers in Saudi Arabia. Since the World Health Organization (WHO) declared the novel coronavirus COVID-19) as a pandemic on 11 March 2020, its spread continues throughout the world, with newer genetic variants regularly appearing from different parts of the world 9 as a pa. UnfortuSince the beginning of the pandemic, KSA had put very active steps in controlling the pandemic. Soon after the release of the results of the Phase III clinical trial with the Pfizer-BioNTech COVID-19 vaccine, it was approved by the Saudi authorities for use . COVID-1Vaccine hesitancy for a COVID-19 vaccine booster is a public health challenge. Morbidity and mortality associated with the spread of the Omicron variant can be reduced by an increased acceptance of the COVID-19 booster dose strategy, especially among the high-risk population including HCWs. However, emerging evidence suggests that vaccine hesitancy for a COVID-19 vaccine booster dose is present among a considerable proportion of the fully vaccinated general public . A recenTM forms. This study was conducted from 1 October 2021 to 30 November 2021. The Saudi government announced the availability of the COVID-19 booster dose for high-risk individuals including healthcare workers on 20 October 2021, and the COVID-19 booster dose became available for everyone above the age of 18 on 7 November 2021. The institutional ethical committee has approved this study with approval number UJ-REC-027. The STROBE guidelines for cross-sectional studies were followed while reporting this study’s findings [The present study was an online survey using the snowball technique to recruit participants using GoogleThe questionnaire was prepared in English along with its Arabic translation. The translation of the questionnaire was performed according to the standard procedure involving independent bilingual experts. The questionnaire was pilot tested among 20 participants before the beginning of the study. The questionnaire’s link was shared with the author’s social media contacts in the health sector . The intention to receive a COVID-19 booster dose was rated using a four-point scale . The vaccination preference was also rated using a four-point scale (completely confident to completely non-confident).The fourth part of the questionnaire was related to the health belief model (HBM) in the context of the COVID-19 illness and booster vaccination [t-test. Binary logistic regression using the vaccination intention as the dependent variable was utilised to analyse the HBM construct predictors of COVID-19 booster dose uptake. The model fit of logistic regression analysis was tested using the Hosmer–Lemeshow goodness-of-fit test. The forward LR method of regression was used to obtain odds ratios (OR) and 95% confidence intervals (95% CI). The statistical significance level was kept at p < 0.05.The Statistical Package for Social Sciences  software was employed in data analysis. The characteristics of the study population were explored using descriptive statistics. The statistical significance among study variables was analysed using chi-square tests as well as independent sample This study received 2059 complete responses. Health beliefs about the susceptibility for COVID-19 infection were mixed for the study participants. Of all participants, 64.2% disagreed with the statement regarding the greater chance of getting infected with COVID-19, and only 40.2% reported their worries regarding the higher chance of getting COVID-19. However, 74.7% of survey participants still thought that acquiring COVID-19 is a possibility for them right now. The study participants had relatively higher health belief perceptions regarding the severity of the COVID-19 infection. Of all participants, 84.2% agreed that the COVID-19-related complications are serious, and 57% still admitted their fear of getting COVID-19 infection. However, only 28.3% agreed that getting COVID-19 will make them severely sick. The benefits of COVID-19 booster dose vaccination were viewed positively by the trial participants. Of the participants, 54.7% agreed with the statement that the booster COVID-19 vaccination is a good step to reduce their fear of catching COVID-19, and 69.3% agreed that receiving the booster COVID-19 vaccine decreases their chances of catching COVID-19 infection and its complications. The study participants expressed fewer perceived barriers to COVID-19 booster dose vaccination. A total of 46.1% were concerned with the possible side effects, 43.1% were concerned with the efficacy of the COVID-19 booster dose vaccination, 37.9% expressed concerns regarding the safety of the COVID-19 booster dose vaccination, and 34.2% expressed concern regarding faulty/fake COVID-19 booster dose vaccination. Regarding cues to action, 75.4% of the study population reported that they would take the booster dose of COVID-19 vaccine only if they were given adequate information about the vaccine, and 62% reported that they would only take it provided the booster dose was taken by many healthcare workers in Saudi Arabia. p = 0.001), with more people choosing locally manufactured vaccines. There was also a statistically significant association between vaccine preference and confidence in the foreign-made vaccines , with a higher number of respondents who reported confidence in foreign-made vaccines preferring foreign-made vaccines. Males , non-Saudi nationals , education level masters and above , monthly income more than SAR 15,000 , and those with family history of COVID-19 infection  expressed significant preference for foreign-made vaccines. The findings are summarised in A majority of the study participants (64.5%) expressed their confidence in the domestically made COVID-19 vaccine. However, a higher proportion (80.6%) reported their confidence in the foreign-made/imported vaccines. Of the participants, 47.6% expressed a preference for foreign-made COVID-19 vaccines, whereas only 14.2% expressed a preference for domestically made vaccine. There was a statistically significant link between vaccination preference and confidence in local vaccines  reported their intention for the COVID-19 booster dose uptake: 39.8% responded definitely yes and 31.3% responded probably yes. On the other hand, 17.4% of the respondents expressed that they were probably not intending to receive the COVID-19 booster dose uptake, and 11.5% also responded with definitely no intention for COVID-19 booster dose uptake. p < 0.001). There was also significant association between definite intention to receive a COVID-19 booster dose and nationality , marital status , education level , monthly income , and co-morbid medical illness . The findings are summarised in p < 0.001). There was a significant association between the constructs in the HBM model and COVID-19 vaccine (booster) intention. The findings are summarised in In the chi-square test, there was a significantly higher definite intention for COVID-19 booster dose uptake among males  dose of COVID-19 vaccine as a good idea to decrease fears regarding getting COVID-19  and perceptions that receiving the booster dose reduces the risk of getting COVID-19 or its complications , under the perceived benefit construct, were the strongest predictors of a definite intention to receive a COVID-19 booster dose. Being concerned with safety  under the perceived barriers construct was the strongest significant correlate of having no definite intention to take the COVID-19 vaccination. The findings are summarised in This study found that overall, 71.1% of the study population reported their intention for COVID-19 vaccination booster dose uptake, and a definite intention was reported by 39.8%. The results of the present study are in agreement with similar published studies. A cross-sectional survey among HCWs from Czechia reported that 71.3% reported positive intention for a booster dose of COVID-19 vaccination uptake . AnotherIn addition, factors influencing the intention to receive a third (booster) dose of COVID-19 immunisation and the role of the HBM in predicting vaccination intention among KSA healthcare workers (HCW) were investigated in this study. The study was started before the Saudi government approved the COVID-19 booster dose vaccination for HCW. The findings of the present study showed that HBM constructs of perceived benefit and perceived barriers significantly predicted COVID-19 booster dose vaccination uptake. However, the other HBM constructs  did not significantly influence the definite intention for the third (booster) dose of COVID-19 vaccination among HCWs in the KSA. To the best of our understanding, no published studies are available exploring COVID-19 booster uptake intention using HBM. However, previous studies that analysed COVID-19 vaccination intention using HBM also reported similar results. Similar to our study results, a Malaysian study reported that the HBM constructs  significantly predicted a definite intention for COVID-19 vaccination uptake . A recenThe study results showed that perceptions regarding the susceptibility to COVID-19 and worries regarding the likelihood of getting COVID-19 infection were less among the majority of the study population. One of the reasons for the lower level of perceived susceptibility among HCWs could be that the majority of them were fully vaccinated and the rate of COVID-19 infection in KSA at the time of the study was significantly less. However, lower perceived susceptibility for COVID-19 infection might lead to less compliance with preventive measures against COVID-19 infection . There iThis study’s results also showed that males, older participants, higher educational achievers, and respondents belonging to the high-income category had more acceptance for the COVID-19 booster dose vaccination, which is consistent with the published literature. Pal et al. explored attitudes towards the COVID-19 booster dose vaccine among US HCWs and found that younger age and lower level of educational attainment were associated with higher vaccine hesitancy . AnotherThere are numerous limitations to this study that must be considered when evaluating its findings. The present study utilised an online survey methodology to collect data, and such study designs are prone to selection bias. The HCWs were inquired regarding the behavioural intention for COVID-19 booster dose vaccination uptake in this study, which may not reflect actual behaviour. Various confounding factors which might influence vaccination hesitancy such as co-morbid psychiatric symptoms were not included in this study. A number of factors that could predict hesitancy toward receiving vaccines, such as adverse events after previous vaccine administration, being pregnant, and hesitancy toward other types of vaccines, were not included in this study. Finally, the questionnaire did not investigate COVID-19 vaccine anamneses.This study found that 71.1% of the study population reported their intention for COVID-19 booster dose vaccination uptake. Moreover, we also found that many HBM constructs predict vaccination intention for COVID-19 booster dose among HCWs in the KSA, which can be utilised to promote COVID-19 booster vaccination among HCWs.