The Lockdown Impact Scale for Students (LISS)

Background: The Covid-19 pandemic has resulted in many student populations learning online in lockdown. While the mental health consequences of lockdown are increasingly understood, the core features of ‘cabin fever’ are poorly described. Methods: We conducted a questionnaire survey of 649 undergraduate medicine and health sciences students. Item content was developed based on current literature and input from student representatives. Results: Mokken scaling identified seven questions that together formed a strongly unidimensional scale which comprised two domains : social isolation/cabin fever and demotivation / demoralisation. Scale scores were significantly associated with depression, self-rated mental health, impaired study efficacy and doomscrolling. Conclusions: The adverse effects of lockdown on student wellbeing appear to be driven to an important extent by an experience of isolation and demotivation that correspond to narrative descriptions of cabin fever. In the foreseeable event of future pandemics, these experiences are a promising target for health promotion in students studying in lockdown.

The Crit coefficient in Mokken scale analysis: a simulation study and an application in quality-of-life research

Purpose In Mokken scaling, the Crit index was proposed and is sometimes used as evidence (or lack thereof) of violations of some common model assumptions. The main goal of our study was twofold: To make the formulation of the Crit index explicit and accessible, and to investigate its distribution under various measurement conditions. Methods We conducted two simulation studies in the context of dichotomously scored item responses. We manipulated the type of assumption violation, the proportion of violating items, sample size, and quality. False positive rates and power to detect assumption violations were our main outcome variables. Furthermore, we used the Crit coefficient in a Mokken scale analysis to a set of responses to the General Health Questionnaire (GHQ-12), a self-administered questionnaire for assessing current mental health. Results We found that the false positive rates of Crit were close to the nominal rate in most conditions, and that power to detect misfit depended on the sample size, type of violation, and number of assumption-violating items. Overall, in small samples Crit lacked the power to detect misfit, and in larger samples power differed considerably depending on the type of violation and proportion of misfitting items. Furthermore, we also found in our empirical example that even in large samples the Crit index may fail to detect assumption violations. Discussion Even in large samples, the Crit coefficient showed limited usefulness for detecting moderate and severe violations of monotonicity. Our findings are relevant to researchers and practitioners who use Mokken scaling for scale and questionnaire construction and revision.

Combining EQ-5D-5L items into a level summary score: demonstrating feasibility using non-parametric item response theory using an international dataset

Background The EQ-5D-5L is a well-established health questionnaire that estimates health utilities by applying preference-based weights. Limited work has been done to examine alternative scoring approaches when utility weights are unavailable or inapplicable. We examined whether the Mokken scaling approach can elucidate 1) if the level summary score is appropriate for the EQ-5D-5L and 2) an interpretation of such a score. Methods The R package “mokken” was used to assess monotonicity (scaling coefficients H, automated item selection procedure) and manifest invariant item ordering (MIIO: paired item response functions [IRF], HT). We used a rich dataset (the Multiple Instrument Comparison, MIC) which includes EQ-5D-5L data from six Western countries. Results While all EQ-5D-5L items demonstrated monotonicity, the anxiety/depression (AD) item had weak scalability (Hi = 0.377). Without AD, scalability improved from Hs = 0.559 to Hs = 0.714. MIIO revealed that the 5 items can be ordered, and the ordering is moderately accurate in the MIC data (HT = 0.463). Excluding AD, HT improves to 0.743. Results were largely consistent across disease and country subgroups. Discussion The 5 items of the EQ-5D-5L form a moderate to strong Mokken scale, enabling persons to be ordered using the level summary score. Item ordering suggests that the lower range of the score represents mainly problems with pain and anxiety/depression, the mid-range indicates additional problems with mobility and usual activities, and middle to higher range of scores reveals additional limitations with self-care. Scalability and item ordering are even stronger when the anxiety/depression item is not included in the scale.

Spousal Violence: A Mokken Scaling Analysis of Attitudes of South Asian Men and Women

Attitudes toward intimate partner violence (IPV) are usually explored by asking participants to respond to some statements describing various instances or situations. Currently, we do not know if responses to such questions or statements are random, leading to a total score which is hard to compare between respondents, or in a hierarchical manner which makes such comparison much more meaningful. The study was conducted to explore the structure of an “attitudes to intimate partner” violence scale used in the Demographic and Health Surveys Program (DHS), for a hierarchy of items according to the criteria of Mokken scaling. Secondary analyses of the data related to attitudes to IPV of South Asian men and women, collected by the DHS from Pakistan, India, Bangladesh, Maldives, and Nepal between 2006 and 2014. A strong Mokken scale was apparent in the data with IPV by men being most justified in cases where the wife neglected the children and least endorsed in the case of refusing to have sex. Men and women endorsed the items in the same order, but some inter country differences were apparent.

On the Practical Consequences of Misfit in Mokken Scaling

Mokken scale analysis is a popular method to evaluate the psychometric quality of clinical and personality questionnaires and their individual items. Although many empirical papers report on the extent to which sets of items form Mokken scales, there is less attention for the effect of violations of commonly used rules of thumb. In this study, the authors investigated the practical consequences of retaining or removing items with psychometric properties that do not comply with these rules of thumb. Using simulated data, they concluded that items with low scalability had some influence on the reliability of test scores, person ordering and selection, and criterion-related validity estimates. Removing the misfitting items from the scale had, in general, a small effect on the outcomes. Although important outcome variables were fairly robust against scale violations in some conditions, authors conclude that researchers should not rely exclusively on algorithms allowing automatic selection of items. In particular, content validity must be taken into account to build sensible psychometric instruments.