Reliability and validity of a Japanese version of life-space assessment in institutionalized settings

Abstract

Purpose: A reduction in life space (LS) is associated with a negative impact on medical and functional status during hospitalization, with potential consequences after discharge. A validated version of an evaluation tool for assessing LS in Japanese individuals in an institutionalized setting is lacking. This study developed and validated a Japanese version of the Life-Space Assessment in Institutionalized Settings (LSA-IS-J). Material and methods: The LSA-IS-J was developed using a specified process. This study included 30 inpatients admitted to the rehabilitation ward. The Timed Up and Go Test, Berg Balance Scale scores, 10-meter walking time, Functional Independence Measure, and Falls Efficacy Scale-International were used to assess construct validity. For test-retest reliability, the same assessor evaluated the LSA-IS-J within two days. Correlation coefficients were calculated to determine the construct validity. Results: The mean LSA-IS-J total score mean was 37.7 (standard deviation: 7.4), with skewness of -0.17 and kurtosis of -1.39. No ceiling or floor effects are observed. The test-retest reliability was excellent for the total and subtests, with intraclass correlations ranging from 0.78 to 0.99. The LSA-IS-J showed significant correlations with almost all variables related to motor status and concerns about falling, indicating high construct validity. In contrast, more generic variables were not significantly associated. Conclusions: The LSA-IS-J demonstrated broad feasibility for assessing LS without ceiling or floor effects among patients undergoing ward-based rehabilitation. The LSA-IS-J also demonstrated excellent test-retest reliability and adequate construct validity for constructs with a high impact on LS.

Keywords

• Life-space assessment
• Life-space assessment in institutionalized settings
• Reliability
• Validity