Supplementary Material for: Comparing cost and acceptability two instruments to measure instrumental activities of daily living in older people in Chile

Introduction: Population aging and increasing in long-term care needs call for designing and implementing better tools for assessing functional ability. In Chile, the Lawton & Brody (L&B) scale is used for identifying limitations with instrumental activities. This study compares the costs and acceptability of the L&B with a new instrument to measure IADL: the Instrument for the Assessment of Functionality Stages (IDEEF). Methods: Phone surveys were carried out to apply the L&B and the IDEEF to a sample of 200 older people (60+) participating in public programs for older people in the Metropolitan Region, Chile. Besides the items assessed by each scale, the survey captured completion times and included a short questionnaire on acceptability, data that allowed comparisons between instruments. Results: On average, the L&B takes around 4 minutes to be applied; the completion times for the IDEEF are four times longer. However, the IDEEF performs better in terms of acceptability and has neither gender bias nor dependency bias. Conclusion: Both instruments have pros and cons but the IDEEF appears as a feasible alternative to the L&B to improve the assessment of IADL in the country.