CLEAN FRONTLINE CAMBODIA A Stepped Wedge Cluster Trial of an Environmental Hygiene Educational Intervention Across Thirteen Cambodian Hospitals
Phase: NA
Conditions: Hospital Infections, Environment, Controlled, Infection Control
Sponsor: London School of Hygiene and Tropical Medicine

 
 
 
 
 
 
 
 
 
CLEAN FRONTLINE CAMBODIA 
A Stepped Wedge Cluster Trial of 
an Environmental Hygiene Educational Intervention 
across Thirteen Cambodian Hospitals 
 
 
 
A STUDY PROTOCOL 
NCT number: 26637 
 
Date: 07-02-2022 
 
 
 

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Table of Contents 
 
Executive Summary ................................................................................................................. 3 
List of abbreviations ................................................................................................................ 4 
1 
Background ...................................................................................................................... 5 
2 
Objectives ........................................................................................................................ 5 
3 
Methods ........................................................................................................................... 6 
3.1 
Study design ............................................................................................................. 6 
3.2 
Study sites and population ...................................................................................... 6 
3.3 
The intervention ...................................................................................................... 7 
3.3.1 
Preparatory stage ............................................................................................. 7 
3.3.2 
Training stage ................................................................................................... 8 
3.3.3 
Supervision stage ............................................................................................. 8 
3.4 
Evaluation of the intervention and expected outcome ......................................... 8 
3.4.1 
Process evaluation ........................................................................................... 9 
3.4.2 
Impact evaluation ............................................................................................. 9 
4 
Data  and reporting ....................................................................................................... 13 
5 
Ethical approval and consent ........................................................................................ 13 
6 
Quality assurance and risk mitigation .......................................................................... 13 
Appendices ............................................................................................................................ 13 
References ............................................................................................................................. 15 
 

Executive Summary 
Environmental hygiene is a key component of infection prevention in healthcare, and a driver of 
healthcare associated infections. Staff who clean in many low resource countries receive no formal 
training on cleaning, waste disposal and linen handling. This issue has been exacerbated by the 
COVID-19 pandemic. The only recommended training on environmental hygiene for low resourced 
facilities, TEACH CLEAN, uses a training of trainers model. A selected cadre of “champions” is trained 
which in turn train their peers with responsibilities on environmental hygiene at the facility level. 
Early pilot data to test its effectiveness of this training package are very promising. 
 
 
The main objective is to evaluate the effectiveness of an environmental cleaning bundle to improve 
microbiological cleanliness in Cambodian hospitals.  
 
TEACH CLEAN will be implemented across all hospitals (13) of three provinces in Cambodia. A 
stepped wedge randomised trial will be used to evaluate the effectiveness of TEACH CLEAN to 
improve microbiological cleanliness in Cambodian hospitals. All facilities will receive the 
intervention. Hospitals are arranged in groups of three or four based on the randomisation with 
staggered commencement dates of the intervention at four distinct time points. The design will 
include ten months of data collection. We expect one month gap between the training of champions 
and the training of staff at the facility level. The main outcome is microbiological cleanliness (<2.5 
cfu/cm2 = clean ; ≥2.5 cfu/cm2 = not clean) measured using a non-specific agar on one side for 
measuring total Aerobic Colony Counts (ACC/cm2). With 30 sampling sites in each hospital and with 
a pre-training cleanliness proportion ranging from 30% to 50% will give us over 85% power to detect 
a 10% absolute post-intervention increase in cleanliness. 
 
Evidence from this trial will contribute to future policy and practice guidelines about hospital 
environmental hygiene and ultimately reduce healthcare associated infections. This would be the 
first randomised trial on environmental hygiene in low resource settings. 
 
 
 

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List of abbreviations 
 
 
AMR 
: Antimicrobial Resistance 
DHS 
: Department of Hospital Services, Ministry of Health 
FGD 
: Focus Group Discussion 
HAI 
: Healthcare Associated Infection 
IPC 
: Infection Prevention and Control 
LMICs 
: Low- and Middle-Income Countries 
LSHTM 
: London School of Hygiene and Tropical Medicine 
MoH 
: Ministry of Health 
NECHR 
: National Ethics Committee for Health Research 
NIPH 
: National Institute of Public Health 
ToT 
: Training of Trainers 
 
 

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1 Background  
Healthcare-associated infections (HAIs) represent a significant burden in low-and middle-income 
countries (LMICs), with rates are at least twice as high as on the European continent (1). 
Environmental cleaning is one of the core pillars of infection prevention and control (IPC) across 
healthcare facilities. The COVID-19 pandemic has thrown renewed attention to the linkages between 
hand and environmental hygiene, and the need to tackle both to reduce transmission (2,3), so 
bringing added benefits for preventing HAIs and mitigating antimicrobial resistance (AMR). There are 
many challenges to rapidly improving hand and environmental hygiene given the weak state of 
water, sanitation and waste management infrastructure in healthcare institutions, and emergency 
responses to COVID-19 need to provide both immediate solutions and options bringing sustained 
and longer-term benefits (4). The COVID-19 pandemic has severely affected Cambodia with a total of 
over 120,000 cases and substantial disruption to the healthcare system. Strengthening infection 
prevention is needed to support the healthcare system response to the pandemic. 
Training of key workers in environmental hygiene – those whose primary role is cleaning (here called 
cleaners) – is one of such response mechanisms which brings immediate and lasting gains, and 
practical guidance on reducing environmental transmission in the face of infrastructural, equipment 
and supply bottlenecks. These frontline workers are crucial in the face of massive shortages of 
healthcare professionals, and where overcrowding in healthcare facilities increases risk of 
transmission from frequent hand-touch fomites. Cleaners in LMICs are often untrained, poorly 
supervised, and unprotected, and their low levels of literacy present particular challenges for 
learning modalities (4–6).  
Currently in Cambodia, there is no routine formal training of cleaners. The sporadic training sessions 
that have been organised are insufficient and suboptimal in quality. To bridge this gap in 
environmental hygiene training, the National Institute for Public Health (NIPH) together with the 
Cambodian Ministry of Health’s Department of Hospital Services (DHS), and WaterAid Cambodia 
decided to provide training on environmental hygiene to frontline cleaners from 13 public hospitals 
in Cambodia using an internationally recognised package of training on environmental hygiene: 
TEACH CLEAN (https://www.lshtm.ac.uk/research/centres/march-centre/soapbox-
collaborative/teach-clean) (7). Environmental hygiene training has never been formally evaluated in 
the low resourced contexts, although pilot evaluation in other contexts show promising results (8). 
The more recent version is currently being adapted by the WHO for global roll out.  
In collaboration with NIPH, DHS, WaterAid, the research team at the London School of Hygiene and 
Tropical Medicine (LSHTM) aims to thoroughly evaluate this roll out. The study described below 
represents the first randomised trial in a low-resource setting testing an environmental hygiene 
education intervention.  
2 Objectives 
The main objective is to evaluate the effectiveness of an innovative environmental cleaning bundle, 
TEACH CLEAN, as an intervention to improve microbiological cleanliness in Cambodian hospitals. 
More specifically, this study aims to:  
• 
Assess whether the quality of microbiological cleanliness (primary outcome) changes as a 
result of the intervention 
• 
Assess whether in absence/presence of S. aureus/MRSA changes as a result of the 
intervention 
• 
Explore knowledge, self-efficacy and social norms  among cleaners and investigate whether 
they vay by the degree of implementation strength, and possibly by level of microbiological 
cleanliness 

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• 
Explore the association between the degree of implementation strength and microbiological 
cleanliness 
It is expected that an effective and tailor-made environmental cleaning bundle will be taken up and 
integrated in national training programs and guidelines on environment cleaning and hygiene in 
healthcare facilities and further scaled up in Cambodia. Ultimately, this will contribute to reducing 
healthcare associated infections in the country and globally through sharing of such innovative 
training package.        
3 Methods  
3.1 
Study design  
This is a randomised controlled trial using a stepped-wedge random allocation with the following 
details: 
• 
The environmental hygiene intervention will be rolled out to thirteen hospitals over ten 
months  
• 
The main intervention – the training of trainers/champions (ToT) will be delivered to 
selected cleaning champions from three or four hospitals within a certain month (within the 
same 4 weeks of at a specific month in the schedule), hence there will be a total of 4 steps (4 
main periods when training happens) 
• 
The timing allocation for hospitals matched with the four training periods is random 
• 
The results across unexposed observation periods are compared with that across the 
exposed observation period  
• 
The stepped-wedge design, with staggered timings for the start of the intervention and 
intervention length (2 to 8 months), supports feasibility while maintaining the rigour of the 
study.  
• 
The design allows the NIPH and its partners to work with a group of hospitals at the time to 
maximise quality and consistency of the implementation, and avoid having to manage the 
changes across 13 hospitals simultaneously 
This is the suitable design to ensure that all the 13 participating hospitals receive the 
interventions as proposed by NIPH and its partners whilst keeping the rigor of randomisation 
based on timing. 
3.2 
Study sites and population  
This study will be conducted in thirteen hospitals in three selected provinces in Cambodia. These 
hospitals have the following characteristics: 
• 
District and provincial referral hospitals in the selected provinces 
• 
Public hospitals  
• 
46% of them have an operating theatre 
• 
Range of hospital beds: 30 -220 
• 
Ensuring representation in at least three provinces of the country. The three provinces are 
selected based on a mix of the prior work conducted by WaterAid in those areas, and  
aiming to select largest referral hospitals in the country. See Table 1 for key characteristics 
of these provinces 
 
 

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Table 1. Region characteristics 
 
% rural (vs urban) 
Pop density 
Income (GDP per 
capita, 2015) 
Kampong Chhnang 
85.5% 
95 
2,726  
Battambang 
76% 
84 
2,881 
Kratie  
90% 
34 
2,765 
Source of information:  
http://hdr.undp.org/sites/default/files/nhdr_cambodia.pdf  
https://www.nis.gov.kh/nis/Census2019/Provisional%20Population%20Census%202019_English_FINAL.pdf  
https://www.adb.org/sites/default/files/institutional-document/151706/cambodia-country-poverty-analysis-
2014.pdf 
 
In Cambodia, there are twenty-five provinces. Battambang is one of the top seven most populous 
provinces, which consists of 987,400 people in 2019. Besides a large population, Battambang is a 
prosperous province for being the leading rice-producing province; it is also an economic corridor 
that connects Cambodia and Thailand. Kampong Chhnang has 525,932 people living in the province, 
while there are only 372,825 people situated in Kratie in the same year. With a lesser population, 
Kampong Chhnang and Kratie are listed among the seven poorer provinces in Cambodia, according 
to Cambodia Poverty Analysis 2014. 
3.3 
The intervention 
TEACH CLEAN is an intervention aimed at improving environmental hygiene in hospitals in 
low-resource settings. It was created by the Soapbox Collaborative jointly with NHS Grampian (UK) 
based on international guidelines for environmental hygiene. It was pilot-tested in The Gambia in 
2016 and Tanzania 2018, and used in India and Cameroon among others. Key features include 
participatory methods and pictorial guidelines to facilitate learning for hospital cleaners, who 
typically have low education and literacy levels (5,9,10). The CLEAN Frontline study will use the most 
up to the data version of the package which has been updated recently by the WHO for global roll 
out. TEACH CLEAN comprises the following stages:  
3.3.1 
Preparatory stage (phase 1)  
This stage includes engagement with hospital managers, selection of facility cleaning champions in 
each hospital; assessment of environmental hygiene status and resources; and adaptation of TEACH 
CLEAN to the local context. 
A situation analysis and basic needs assessment will be conducted to collect necessary data and 
information for preparation and adaptation of the intervention to the local context – 
contextualization of the intervention through analysis of relevant policy documents and a rapid 
facility survey. For the latter, trained surveyors will pay a visit to all the 13 hospitals. During the visit, 
the surveyors will conduct interviews with hospital and ward leaders responsible for IPC and 
cleaning, using a semi-structured questionnaire (Appendix 1 – available on request). In addition, a 
hospital walkthrough will be done to observe the cleaning and hygiene facilities and practices using 
an observation checklist (Appendix 2- available on request ). The collected data will be analysed and 
the findings will be used to  
• 
identify relevant wards and cleaning champions for the intervention,  
• 
map ward specific sites for environmental swabs (with dipslides) and  
• 
adapt the training tools and process to align with existing policies/guidelines, needs and 
feasibility, including the feasibility of using digital technologies for the training.  

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A tailored intervention should optimise bundle implementation and compliance, but such tailoring 
will not compromise the integrity of the individual components and the ‘sum of the whole’ of the 
bundle.  
3.3.2 
Training stage (phase 2) 
This stage is primarily a training of facility cleaning champions to educate and supervise other existing 
facility cleaners with environmental hygiene responsibilities – training of trainers (ToT). Cleaning 
champions are selected on the basis of having a supervisory or senior role within the ward, prior 
understanding of infection prevention in relation to environmental hygiene, good communication 
skills and willingness to develop knowledge and take on the role of champion. 
The identified facility cleaning champions will be trained as trainers to further train other facility 
cleaners and staff who are involved in cleaning in the form of training of trainers (ToT). The training 
content includes as much as possible the seven contextualized modules of TEACH CLEAN training 
package (CLEAN BOX): i) Introduction to Infection Prevention and Control, ii) Personal hygiene and 
dress code, iii) Hand hygiene, iv) Personal protective equipment, v) Housekeeping/control of 
environment, vi) Waste handling, and vii) Linen handling.  
The seven TEACH CLEAN training modules cover cleaning agents, frequency of cleaning, 
cleaning techniques, importance of environmental hygiene for HAI prevention, and, specifically for 
champions, techniques for supervising staff and methods for attracting sufficient resources. The 
TEACH CLEAN bundle is currently the only cleaning training for hospitals in resource-limited settings 
endorsed by several international guidelines including the recent “Best Practices for Environmental 
Cleaning in Healthcare Facilities: in resourced-limited settings” (7). The CLEAN Frontline study will 
use the most up to the data version of the package which has been updated recently by the WHO for 
global roll out. 
NIPH in collaboration with DHS will contextualize and deliver the interventions. 
The contextualized TEACH CLEAN will be offered primarily to the three selected wards identified at 
the preparatory stage: i) maternity ward, including labour and post-natal rooms, ii) general medicine 
ward, iv) and paediatric ward. 
The timing and duration of the training will be organised with the hospital and ward manager to 
ensure staff are able to attend whilst maintaining key core personnel in the wards, and to allow for 
flexibility with staff personal commitments. 
3.3.3 
Supervision stage (phase 3) 
This stage refers to ongoing mentorship by DHS of cleaning champions while they educate and 
supervise existing facility cleaners with environmental hygiene responsibilities. The trained cleaning 
champions are expected to train other facility cleaners and staff who are involved in cleaning. This 
requires regular field supervisions and distance support by master trainers to monitor their progress, 
identify the challenges they face in providing training to other cleaners, and help them address such 
challenges, including technical support and provision of basic and necessary materials for training and 
environmental cleaning.     
3.4 
Evaluation of the intervention and expected outcome 
The evaluation aims to ultimately measure the effectiveness of the environmental cleaning bundle 
(the intervention) in improving the ‘microbiological’ cleanliness of the study hospitals – the primary 
outcome of the intervention. This expected outcome will not only depend on the package of 
intervention but also on how the package will be delivered. Crucially, the trial will provide 
meaningful results about the effect of the training stage (phase 2) and supervision stage (phase 3). 
The preparatory stage (phase 1)cannot be evaluated as it will commence virtually simultaneously 
across the hospitals. Therefore, a process evaluation is needed at the training and supervision stage. 

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3.4.1 
Process evaluation 
A process evaluation conducted by the Cambodia WaterAid team together with the LSHTM team will 
aim to capture information around the following aspects of implementation as recommended by the 
Medical Research Council (UK) guidelines for process evaluations of complex interventions: 
implementation fidelity, dose, mechanisms, reach and context: 
• 
Implementation fidelity will be measured through semi-structured observations of trainings 
at the ToT level and facility level – we will aim for at least one set of training to be observed 
in each facility (N=13-26 trainings observed) and using interviews and focus group 
discussions (FGDs) with stakeholders by an experienced qualitative researcher (see Appendix 
3 and Appendix 4). Phone interviews will be conducted with a sample champions and 
cleaners at regular intervals across the study to assess both implementation fidelity in terms 
of supportive supervision and contextual changes described just below (See Appendix 3 and 
Appendix 4).  
• 
With regards to context, we will map the hospital characteristics and context (e.g. staffing, 
size), infection prevention policies and practices (e.g. antimicrobial stewardship, antibiotic 
use, screening) and other relevant activities (e.g. cleaning staff changes, policy changes) 
within the hospital in a qualitative way through stakeholders interviews (see Appendix 3). 
Ongoing reviews of contextual information throughout the intervention at each site will 
assist with trial site comparisons, replication and scalability and knowledge translation  
• 
Dose and reach of the intervention will also be monitored e.g. number of modules 
delivered, number of facility staff trained, number of supervision sessions. This information 
will be collected using training records.  
• 
Data on mechanisms (e.g. increase in knowledge) through which the intervention is believed 
to work will also be collected through a quantitative survey enquiring about knowledge, 
social norms, network structure and self-efficacy measures. See Appendix 5 for the draft 
survey. The survey will be administered to all staff who cleans in the selected facilities at the 
end of the trial will allow us to compared knowledge and attitudes scores between control 
and intervention clusters. This is particularly important to gauge whether the bundle has 
impacted not only upon behaviour but also on and knowledge, which are the longer-term 
drivers of behavioural outcomes.  
• 
All these data collection tools for the process evaluation have been previously used in the 
former pilot work of TEACH CLEAN (8). 
All process evaluation tools (Appendix 3, 4 and 5) are currently in a draft format and will need to 
be piloted and refined in an iterative way according to the early qualitative results of the study.  
 
3.4.2 
Impact evaluation 
 
Randomisation: Hospitals will be randomly allocated to intervention timing 3 months prior to the 
start of the first training. We will use constrained randomisation to ensure there is a balance in key 
hospital characteristics in each randomisation step. Specifically, randomisation will be constrained 
based on region and hospital size using standard methods (11). One of the investigators will be in 
charge of computer generation of the allocation in terms of time and hospital identifiers. 
Alternative, we will generate a random allocation using a public method with the key study 
coordinators (NIPH, WaterAid, DHS and LSHTM) of picking from “a hat” and including all key 
investigators in this process virtually, but keeping the constrained rules described just above.  
 
 

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During the first month of data collection, i.e. 4 weeks before the start of the first ToT, we will 
baseline data collection; some intervention aspects of phase 1 of the TEACH CLEAN package will be 
ongoing 
 
Staff who clean will not be blinded as this is not possible.  
 
 
 
 
 
Figure 1 – Trial structure 
 
 
Cluster unexposed to the intervention  
Cluster in transition period 
Cluster exposed to the intervention 
 
 
Sampling sites: The unit of measurement for microbiological cleanliness is key hand-touch sites – 
patient beds and other equipment around the patient area (e.g. beds, equipment trolley, bedside 
locker) in our study. Formative observation identified these surfaces most frequently touched by 
healthcare workers, closest to the patient, thus providing the greatest risk of pathogen cross-
transmission (12,13). Other studies report these hand-touch sites in hospitals.(7,13)  
 
A picture will be drawn for each ward with the selected surfaces sampled to guide data collection. 
 
Dipslides: are a widely used method for measuring surface microbiological cleanliness, in hospitals 
and elsewhere (14). We will dipslides coated with a non-specific agar on one side for measuring total 
Aerobic Colony Counts (ACC/cm2) and a selective agar on the other (Baird-Parker agar, to determine 
the presence of S. aureus; Dimanco, UK). Both sides are applied consecutively to adjacent areas of 
the sampling site,. Dipslides will be collected from hospitals once a month. They will be transported 
to local laboratory on the day of collection and incubated in aerobic conditions for 14-36 hours 
(exact timing will be stablished after piloting because logistics arrangements can impact on bets 
incubation time) at 37°C. Colonies were enumerated by visual inspection. See Appendix 6 for the 
laboratory protocol details. 
 
March
May
June
July
August
September
October
Novemver
December
January
Feburary
Hospital 
0
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0
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0
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10 Pilot
0
0
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11 Pilot
0
0
0
0
0
0
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1
1
12 Pilot
0
0
0
0
0
0
0
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13 Pilot
0
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0
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0
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1
Period/Month
Training 
group 1
Training 
group 2
Training 
group 3
Training 
group 4

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Data collection: An independent team (not involved in the delivery of the training) will collect 
monthly data from pre-agreed hospital sites. The cluster size i.e. number of sites sampled per cluster 
will be 30 across all wards. The same patient areas will be used in each monthly measurement. 
Where possible, the sampling week will not be the same each month for the hospital to minimise 
bias from study participants. If feasible, we will collect information on water and bleach availability,  
and patient volume at each monthly visit.  
 
Outcome: Proportion of microbiological cleanliness (<2.5 cfu/cm2 = clean ; ≥2.5 cfu/cm2 = not clean) 
will be calculated for each cluster as the number of sites with <2.5 cfu/cm2 out of the 30 sites 
sampled per period/month.  
 
Power calculations for primary outcome: The intervention will be delivered in four steps across 
thirteen hospitals (3 hospitals per step; except for one step with 4 hospitals – see Figure 1), with 30 
sampling sites each and with a pre-training cleanliness proportion ranging from 30% to 50% will give 
us over 85% power to detect a 30% relative increase in microbiological cleanliness. This is based on a 
two-sided 5 % significance level, a two-period decay correlation structure with the following 
conservative estimates of within- period ICC in microbiological cleanliness at 0.03 (previous pilot), 
auto-correlation of observation at 0.6 and cluster auto-correlation at 0.6, and the intervention 
timings shown in Figure 1. The pre- intervention cleanliness proportion, and the within-hospital ICC 
and were estimated using a pilot data from similar level maternity wards in Tanzania as no local data 
is available on microbiological cleanliness; other available evidence on levels of microbiological 
cleanliness confirm in settings with no formal training sow similar levels of hospital cleanliness in low 
resource settings.(8) We assumed one month delay in the treatment effect for the sample size 
calculation to allow for champions to train staff in their own facility. 
 
We used the website (https://clusterrcts.shinyapps.io/rshinyapp/ ) and underlying formula 
operationalised by Hemming et al. (2020).(15) See results in Figure 2. 
 
The power calculations translate into 4,300 dipslides (13 hospitals*30 sampling sites*10 months = 
3,900 + 10% for contingency purposes)  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

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Figure 2. Sample size calculations 
 
 
 
 
 
Data analyses: Aeorobic Colony Counts and S. Aureus outcomes 
• 
The outcome for unexposed observation periods is compared with that across the exposed 
observation periods.  
• 
The key independent variable will be the intervention (yes/no). The intervention variable will 
switch from “no” to “yes” after the first full month of the training 
• 
Characteristics of the individual sites and clusters will be summarised by exposure status so 
to allow consideration of selection biases and lack of balance.  
• 
These characteristics can be compared by randomisation step. This will include the numbers 
analysed, the average cluster size, and cluster characteristics 
• 
A few characteristics of the hospital (e.g. size) will be considered as independent variables as 
these should remain roughly constant throughout the study.  
• 
Each cluster will be analysed according to the actual time when it was “trained” 
independently on when this was planned for. 
• 
Calendar time is associated with both the exposure to the intervention and also possibly the 
outcome, and so is a potential confounder and will be adjusted for in the analysis 
• 
Adjusting for the systematically different observation periods and for clustering in the data 
will be accomplished.  
• 
We will test the residuals of the model to look for autocorrelation over time and will check 
for influential observations.  
• 
The estimated intra-cluster correlation and time effect from the fitted model will be 
reported both for use in the design of future trials and to allow appreciation of any 
underlying confounding effects of calendar time  
• 
We will consider using a small sample correction. 

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In addition, using the same general model we will create a variable indicating the strength of 
implementation which we will use as an alternative exposure variable to the simpler intervention vs 
control variable. We will also explore descriptively time trends for each cluster. Finally, we will 
analyse the knowledge and attitudes descriptively (and by implementation strength and by 
microbiological outcomes) as these measures are only collected at the end of the trial.  
Qualitative data from FGDs and observations will be analysed adopting a generalised qualitative 
approach in which the transcripts were disassembled into low-level descriptive codes and then 
reassembled into themes that may help explain the observed outcomes 
4 Data and reporting 
Please refer to our exhaustive data management plan as in Appendix 7. The Consort 2018 extension 
to stepped wedge randomised trials will be used (16).  
5 Ethical approval and consent 
Our research team will strictly follow ethical procedures, including the submission of the study 
protocol and related tools to the National Ethics Committee for Health Research in Cambodia 
(NECHR) and the ethical review board of LSHTM for review and approval prior to the start. We will 
also respect the voluntary nature of the participation as well as the confidentiality of the 
information provided by the participants. Individual informed consent will be sought from the 
participants prior to data collection. Study information will be posted in all the participating wards 
(See Appendix 8). The consent forms for each data collection piece are available in the appendices 
(Appendices 9-11). 
6 Quality assurance and risk mitigation 
The quality of this study will be ensured by joint efforts of LSHTM and its research partners 
throughout the whole process of the study, from the study design, preparation of the intervention, 
implementation and evaluation. All the engagement with hospital staff for the successful completion 
of the study will follow the principles of Good Clinical Practice. An advisory committee is being 
established to ensure the study follows the highest standards of research quality. 
 
However, this study may encounter a number of challenges and uncertainties. The COVID-19 
pandemic poses extraordinary challenges from the point of view health management and planning. 
With this mind, we are conscious that, in spite of our best efforts, it might not be feasible to conduct 
the trial with the timings as intended during national or local lockdowns prohibited. The team 
behind this study aspires to work together and guided by the Advisory committee adapt to the 
situation as we go along maintaining where possible the study rigour. Other potential limitations of 
the study include willingness to participate, participation fatigue, adverse events occurring at the 
staff, patient or hospital level during the trial, e.g outbreaks of HAIs (COVID-19), seasonal factors, 
organisational or policy changes. This will be mitigated by frequent monitoring of these in each site. 
Participating sites will agree to not implement changes that could impact the trial, e.g. cleaning 
policies or product use, without prior agreement from the study team.  
 
Appendices 
 

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• 
Appendix 1: Questionnaire for interviews with hospital and ward leaders (available on 
request) 
• 
Appendix 2: Observation checklist for hospital walkthrough (available on request) 
• 
Appendix 3: FGD guide 
• 
Appendix 4: Observation of training 
• 
Appendix 5: Questionnaire 
• 
Appendix 6: Lab SOP 
• 
Appendix 7: Data management plan 
• 
Appendix 8: Study information for wards 
• 
Appendix 9: Consent form – trial 
• 
Appendix 10: Consent form – FGD 
• 
Appendix 11: Consent form – questionnaire 
 
 
 

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6736(20)30673-5/abstract 
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Goldman E. Exaggerated risk of transmission of COVID-19 by fomites. The Lancet 
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THE CLEAN FRONTLINE STUDY 
(London School of Hygiene and Tropical Medicine, National Institute of Public Health) 
Study participant information and consent for staff with cleaning duties 
Consent from cleaners 
 
 
To be either read by the respondent, or read aloud by the investigator. The respondent will then 
either sign the consent form or make a thumb print to indicate that they agree to participate in 
the study 
Introduction 
Disinfection of near-patient hospital surfaces is essential to stop Hospital Acquired Infection (HAI) 
occurring.  
 
Purpose of the study 
The CLEAN Frontline study will test whether a training of environmental hygiene can improve 
environmental hygiene on the wards across thirteen Cambodian hospitals.  
 
Your participation in this study is valuable and will provide key insights for the future use of cleaning 
fluids in this context and other low-income facilities. 
 
Details of the study: 
• 
The study will occur in your hospital _________. The training will be provided to staff in the new-
born, maternal, and c-section wards in each of the participating hospitals (13 across Cambodia).  
• 
The training on environmental hygiene will be provided at some point during the 10 months and 
the study team will let the hospital now 4 weeks in advance of the training.  
• 
Each of the participating hospitals will receive the training at key four times during the 10 
months. The timing on which hospital is trained when is chosen at random. 
• 
An evaluation of to assess the impact of the training on environmental hygiene will occur during 
the 10 months.  
• 
No human data is collected during this study 
• 
The study will run for ___ months commencing on the ___ of ____ 
 
Conditions for participation  
You will participate on 1-3 days training on environmental hygiene sometime.  
 

 
Do I have to take part?   
No.  It is up to you to decide to take part or now.  If you don’t want to take part, that’s ok.  Taking part 
is voluntary and you are free to stop the discussion process at any time. If you decide not to take part 
we will respect your decision. We will not ask you why you do not want to participate. There will be 
no complaint or punishment.   
 
Risk or Discomfort  
We do not anticipate any risk to you during this discussion. No information on your personal 
performance will passed on to any of your colleagues or managers. All information we collect is strictly 
confidential and anonymous. 
 
What are the possible benefits?  
We cannot promise the study will help you but the information we get from the study will help our 
and the hospital and the NIPH knowledge and understanding to improve microbiological cleanliness 
in hospital settings.  
Cost/Compensation 
Taking part in this study will not result in any expense to you and no compensation will be provided.  
Contact person for further questions or complaints  
If you have a concern about any aspect of this study you can ask the observer any questions and 
raise any concerns. If they cannot help they will pass the question onto a senior member of the 
team. You may contact directly: 
 
• 
National Institute of Public Health Obscured to ensure phone number privacy 
• 
WaterAid Cambodia – Obscured to ensure phone number privacy 
• 
London School of Hygiene and Tropical Medicine - Obscured to ensure phone number 
privacy 
 
Confidentiality  
All information will be kept strictly confidential. Any information about staff will also be anonymous. 
Your name and any identifying information will not be collected during this discussion.  
 
What will happen to information collected about me?  
All information collected about you will be kept private.  Only the study staff and authorities who 
check that the study is being carried out properly will be allowed to look at information about you.  
Data will be held by NIPH and will be sent to other study staff in London, at the London School of 
Hygiene and Tropical Medicine. Transfer of data is necessary to analyse the data and draw 
conclusions on how to improve environmental hygiene in hospital setting in Cambodia. Aggregate 
level data will also be shared in the public domain for transparency – no individual identifiable data 
is collected as per part of this trial. We will not ask you any identifiable information.  
Voluntary participation   
Taking part is voluntary and you are free to stop your participation at any time. If you decide not to 
take part we will respect your decision. We will not ask you why you do not want to participate. There 
will be no complaint or punishment.   
Permission to continue 
“Do you have any questions for me?” 

 
 
 
 
 
 
 
 
 
 
I, ____________________ (name of the respondent) have read and understood this text, 
understand what is expected of me and all my questions have been answered. I understand that I 
can ask for the observation to stop at any time without giving any reason. I freely accept to 
participate in this study. 
 
___________________       ____________________  Date: _________             
 
Respondent’s name        Signature  
 
 
_______________________         ________________________   Date: ____________             
Witness’s name                             signature  
 
Witness’ signature: A witness’ signature and the thumbprint of the participant or 
nominated person are required only if the staff member is illiterate. If possible, this 
nominated person should be selected by the staff member and should have no connection 
to the study team. 
I have witnessed the accurate reading of the consent form to the potential participant or 
nominated person, who has had the opportunity to ask questions. I confirm that the 
participant or nominated person has given consent freely.  
 
Print name of 
witness: 
 
 
 
 
 
 
Signature of 
witness: 
 
                        Thumbprint of illiterate participant 
 
 
Date: 
 
 
 
 
 
 
If informant has any questions, record questions and your response here: 
_____________________________________________________________________________
_____________________________________________________________________________
_____________________________________________________________________________ 
 

Investigator’s signature: 
I have accurately read or witnessed the accurate reading of the consent form to the 
potential participant or nominated person, who has had the opportunity to ask questions. I 
confirm that the participant or nominated person has given consent freely.  
I confirm that the participant or nominated person has given his/her consent and accepts 
to participate in the study 
Print name of 
investigator: 
 
 
Signature of 
investigator: 
 
 
 
Date: 
 
 
 
 
 
A copy of this informed consent form has been provided to the participant or nominated 
person. |__|__|__| (Initials of the principal investigator/assistant).