Reliability and validity of physical function tests and ADL survey questions in women living in rural, highland Ethiopia

Abstract In rural, highland Ethiopia, physical function, which is the physical ability to fulfill one’s daily roles and responsibilities, may be compromised by a lack of access to nutrition, healthcare, and sanitation. Decreased physical function would be detrimental to health and income-generating activities. Unfortunately, there is a lack of validated methods to measure physical function in adult women in this region. This validity study evaluated the feasibility and reliability of physical tests, including the sit-to-stand (STS) and usual gait speed (UGS). The physical tests were used to assess the validity of context-appropriate activities of daily living (ADL) questions. The results of the STS were used to calculate a power index (Psts) which accounted for body mass and leg length. Feasibility was ascertained qualitatively. Reliability was assessed by comparing the results of the tests and questions between each visit using either Cohen’s κ or Pearson’s ρ. Validity was assessed by regressing the responses to the ADL questions against Psts, controlling for relevant participant characteristics. Study participants consisted of 316 women between the age of 18 and 45 years, living in rural Tigray, Ethiopia, that had previously participated in an impact evaluation of a safety net program. Over a one-week period, participants completed the STS and UGS tests and responded to the ADL questionnaires three times. Psts was determined to be a feasible, reliable, and valid physical function test for women in rural, highland Ethiopia. UGS lacked feasibility and reliability. The validity of the ADLs was inconclusive. The Psts will be an essential tool for improving physical function and, subsequently, health and quality of life in rural Ethiopia.