Why Do Older Korean Adults Respond Differently to Activities of Daily Living and Instrumental Activities of Daily Living? A Differential Item Functioning Analysis

Abstract

The activities of daily living (ADL) and instrumental activities of daily living (IADL) scales represent fundamental measurements of functional status and are important tools not only for planning and predicting the need for long-term care but also for assessing the effectiveness of various policies and services for older populations. 1) Several studies have confirmed the accuracy, validity, and reliability of these functional scales. However, their accuracy as a measure of functioning may be limited by latent biases stemming from cultural differences in who performs different activities.Gender differences in the ADL and IADL tasks have long been postulated. When asked about items related to performing light housework, doing laundry, and preparing meals, men often report that they do not perform these functions due to gender roles. Lawton 2) recognized traditional gender roles as possible confounders Objectives: Culture-based gender norms regarding who performs daily activities can bias the assessment of instrumental activities of daily living (IADL). This study evaluated item-response biases in the activities of daily living (ADL) and IADL among community-living Korean older adults. Methods: The subjects included older Korean participants of the Korean Longitudinal Study ofAgeing baseline survey (n=4,164). We performed differential item functioning (DIF) analysis of these data using the Mantel-Haenszel method. Results: We observed different reported levels of disability for eight IADL items among gender, age, and educational level subgroups. After matching for overall functional disability, men were more likely to report limitations in performing various household activities, compared to cognitive activities in women. Conclusions: Cross-national comparisons of ADL and IADL disabilities need to consider item response bias stemming from culture-based gender norms regarding who performs different household activities.

Older Men Living with Spouse and Older Women Living with Spouse and Children Have Lower Frailty Prevalence: The Korean Frailty and Aging Cohort Study (KFACS)

“…This effect may be another explanation for frailty in men living alone. 34) Thus, cultural factors such as gender roles may have influenced the natural course of frailty.…”

How Can We Evaluate Disability without Bias?

“…These results were consistent with those of a previous research that suggests that households are becoming more egalitarian and that by assuming increasing gender egalitarianism in household tasks, going forward, there should be less potential bias in IADL measures. 12) As proposed by Jang et al, 1) owing to gender bias, the assessment in some studies included only 5-6 items after excluding items not implemented in men. 13) As the initial IADL assessment by Lawton and Brody et al comprised seven items (telephone, transportation, shopping, meal preparation, household chores, taking medicine, and money management), they did not investigate food preparation, housework, or laundry in men.…”

“…We read the article by Jang and Kawachi 1 ) regarding cultural and sexual differences in activities of daily living (ADLs) and instrumental activities of daily living (IADLs) with great interest. The authors concluded that cross-national comparisons of ADL and IADL disabilities need to consider item response bias stemming from culture- or education-based gender differences in household type and cognitive IADLs.…”

“…As proposed by Jang et al, 1 ) owing to gender bias, the assessment in some studies included only 5–6 items after excluding items not implemented in men. 13 ) As the initial IADL assessment by Lawton and Brody et al comprised seven items (telephone, transportation, shopping, meal preparation, household chores, taking medicine, and money management), they did not investigate food preparation, housework, or laundry in men.…”

Tackling Instrumental Activities of Daily Living: Time to Start Rethinking Items

“…Our findings indicated that only two items in the K-IADL (Grooming and Take medications) did not show a response bias. 2) The IADLs were originally designed to assess a more complex range of functioning, in that they require more skill, judgment, and independence than those required for ADLs. They measure an individual's functioning in the social world and the world outside the home.…”