Implementation of quality of life assessment in long-term care

In their systematic review of scales assessing quality of life (QoL) in people living with dementia, Hughes et al. (2019) did not identify any existing instrument applicable for long-term care with sufficient psychometric properties, feasibility, and availability. The most important quality of any instrument is its content validity, which is defined as “the degree to which the content of an instrument is an adequate reflection of the construct to be measured” (p 1160; Terwee et al., 2018). As Hughes et al. (2019) concluded, content validity was only formally evaluated in one of the nine instruments reviewed (QUALIDEM; Ettema et al., 2007). The findings of Hughes et al. (2019) raise two central issues of concern. First, implementing QoL assessments requires certainty that themeasurement is tapping what we are interested in. We need to know if the conceptualizations and items in the instrument reflect the important aspects under study from the view of people living with dementia. Next, lack of proper standardized measurement of QoL is a potential source of error in both clinical settings and research reports. Working in evidence-based practice (Melnyk et al., 2010), this has significant implications for reaching correct conclusions about effective and helpful approaches in any assessment of health interventions. However, as several recent initiatives have focused on developing clinically relevant core outcome sets for people living with dementia, we are optimistic about implementing systematic QoL assessment in long-term care. These initiatives target both issues by recommending standardized assessment packages, as well as ensuring experts living with dementia inform the content validity of these sets of instruments. The COMET initiative (COMET Initiative | Home [comet-initiative.org]) is currently working on and publishing core outcomes important for home-dwelling people living with dementia (Harding et al., 2019; Reilly et al., 2020). ICHOM have developed a standard core outcome set for people living with dementia throughout the disease process (Dementia – ICHOM Connect). While Hughes et al. (2019) used a systematic approach from the Consensus-based Standards for Selection of Health Measurement Instruments (COSMIN) initiative, more refined and comprehensive COSMIN ratings for reviewing patient rated outcome instrument (PROMS) have been published recently (L. B. Mokkink et al., 2017; Prinsen et al., 2018; Terwee et al., 2018). In particular, Terwee et al. (2018) describes a systematic evaluation of content validity, allowing reviewers to evaluate the content validity based on available knowledge about the instruments. We strongly advice researchers and practitioners to attempt this systematic approach, to gain information about the appropriateness of instruments. For PROMS, securing content validity includes the relevance, comprehensiveness, and comprehensibility of the instrument, as evaluated by members of the target group. If evidence of content validity is absent, investigating this by conducting one’s own qualitative interviews or focus groups (Brod, Tesler, and Christensen, 2009) is a better option than developing a new instrument. As Santana-Berlanga et al. (2020) identified 24 instruments assessingQoL applicable for persons with dementia living as “institutionalized older adults”, adding new QoLinstruments to this pool will increase the problem of a lack of systematic measurement and make comparisons in meta-analyses complicated. Investigating the content validity of existing PROMS, where people living with dementia are included as experts, is not only the gold standard (Terwee et al., 2018) but is also something we believe people living with dementia want to contribute to. Participating in research may well provide side effects of feeling useful, empowered, and valued (Øksnebjerg et al., 2018). One part of content validity is “relevance”, and here a central criterion is an appropriate recall period (Terwee et al., 2018). In general, recall bias is a problem for all aggregated retrospect ratings evaluating long-time intervals (Shiffman et al., 2008). For residents in care homes living with moderate to severe dementia, their current emotional state may interfere with the scoring of their past experiences (Kolanowski et al., 2007). Thus, a proper recall period is critical to ensure valid QoL ratings, and several inquiries advocate for momentary assessment to increase validity and decrease the recall bias of self-reports (Clarke et al., 2020; International Psychogeriatrics (2021), 33:9, 861–863 © International Psychogeriatric Association 2021