Abstract
Importance: Typical whole day workload is a metric with potential relevance to the occupational balance and wellbeing of individuals with chronic conditions. Objective: To examine the reliability and validity of using multiple daily NASA Task Load Index measures (whole day TLX) as an indicator of typical whole day workload experienced by adults with Type 1 diabetes (T1D). Design: Participants with T1D completed cross-sectional measures and 2 wk of ecological momentary assessments (EMA) and daily diaries. Reliability was assessed across subgroups (e.g., workers vs. nonworkers); validity was evaluated with multilevel confirmatory factor analysis and with tests of convergent and divergent validity with patient-reported outcomes and blood glucose measures. Setting: Three outpatient endocrinology clinics in the United States. Participants: Data from 164 U.S. adults with T1D (42% Latino, 30% White). Outcomes and Measures: Measures used included the whole day TLX (assessed via 2 wk of daily diaries), time in target blood glucose range (assessed with a continuous glucose monitor), illness intrusiveness (measured cross- sectionally), and stress (measured cross-sectionally and with EMA). Results: Number of days required for at least 0.70 reliability of the average whole day TLX ranged between 2 and 6 days depending on the subgroup. Results supported convergent and divergent validity of the average of the whole day TLX, including associations with average stress (r = .63, p < .001) and time in target blood glucose range (r = -.25, p = .002). Conclusions and Relevance: The whole day TLX was a reliable and valid indicator of typical whole day workload.