Development of short versions for the WHOQOL-OLD module.

PURPOSE OF THE STUDY: To explore short-form versions of World Health Organization Quality of Life (WHOQOL-OLD) with acceptable psychometric properties, which was developed for older adults by the WHOQOL research group, containing 24 items initially. DESIGN AND METHODS: We randomly sampled two-thirds of respondents from the data of WHOQOL-OLD field study (N = 5,566), as a developmental sample, and the remaining third as a validation sample. Three approaches (item response theory [IRT] and regression analysis [REG], classical test theory [CTT] and REG, and CTT and IRT and REG) were performed to develop three short-form scales with six items each using the developmental sample. The reliability and criterion validity of the three short-form scales were evaluated using the validation sample.
RESULTS: The version 1 of short-form scales contained items 6, 11, 12, 16, 20, and 21; version 2 contained items 2, 6, 11, 12, 17, and 22; and version 3 contained items 4, 6, 17, 19, 20, and 24. The correlation coefficient between the total scores of the three versions and WHOQOL-OLD were .918, .925, and .922, respectively. The internal consistency reliability coefficients of the three versions were .681, .678, and .649, respectively. IMPLICATIONS: The three versions of short-form WHOQOL-OLD contained the best items of the original module, much shorter, and with good internal consistency and criterion validity as a whole.