Published online Sep 10, 2015. doi: 10.4239/wjd.v6.i11.1198
Peer-review started: January 19, 2015
First decision: April 10, 2015
Revised: May 29, 2015
Accepted: August 16, 2015
Article in press: August 17, 2015
Published online: September 10, 2015
Processing time: 239 Days and 17.5 Hours
AIM: To initially test for the content validity, comprehensibility, test-retest reliability and internal consistency reliability of the Yin-Yang Assessment Questionnaire (YY-AQ).
METHODS: The process of initial validity and reliability test covered: (1) content validation from the findings of 18 multiple-case studies, validated Yin- and Yang-deficiency assessment questionnaires, relevant literatures and registered Chinese medicine practitioners; (2) comprehension with the levels of comprehensibility for each item categorized on a 3-point scale (not comprehensible; moderately comprehensible; highly comprehensible). A minimum of three respondents selecting for each item of moderately or highly comprehensible were regarded as comprehensive; (3) test-retest reliability conducted with a 2-wk interval. The intraclass correlation coefficients (ICCs) and their 95%CIs were calculated using a two-way random effects model. Wilcoxon Signed Rank test for related samples was adopted to compare the medians of test-retest scores. An ICC value of 0.85 or higher together with P > 0.05, was considered acceptable; and (4) internal consistency of the total items was measured and evaluated by Cronbach’s coefficient alpha (α). A Cronbach’s α of 0.7 or higher was considered to represent good internal consistency.
RESULTS: Eighteen Yin-deficiency and 14 Yang-deficiency presentation items were finalized from content validation. Five participants with type 2 diabetes mellitus (T2DM) performed the comprehensibility and test-retest reliability tests. Comprehensibility score level of each presentation item was found to be moderate or high in three out of the five participants. Test-retest reliability showed that the single measure ICC of the total Yin-deficiency presentation items was 0.99 (95%CI: 0.89-0.99) and the median scores on the first and 14th days were 17 (IQR 6.5-27) and 21 (IQR 6-29) (P = 0.144) respectively. The single measure ICC of the total Yang-deficiency presentation items was 0.88 (95%CI: 0.79-0.99) and the median scores on the first and 14th days were 10 (IQR 6-18) and 14 (IQR 7-23) (P = 0.144) respectively. The results of a descriptive correlation study on 140 survey participants with T2DM using the YY-AQ showed that internal consistency of the total Yin-deficiency and Yang-deficiency presentation items was satisfactory, with Cronbach’s α of 0.79 and 0.78 respectively.
CONCLUSION: The YY-AQ will be tested further for comprehensibility, test-retest and internal consistency reliabilities, scoring system validity, construct validity, convergent and discriminant validities, responsiveness and predictive validity.
Core tip: Unregulated “unhealthy” body constitution (BC) with an imbalanced Yin and Yang can induce chronic diseases. Past research findings support that food has natures that can regulate the “unhealthy” BC by balancing Yin and Yang. Yin-, Yang- and Yin-Yang-deficiency are the common “unhealthy” BC types in diabetes mellitus (DM). In order to identify the “unhealthy” BC presentations, it was necessary for dieticians to develop the Yin-Yang Assessment Questionnaire for DM. It has passed the initial validation and will be tested further for construct validity, convergent and discriminant validities, responsiveness and predictive validity; scoring system validity, comprehensibility, test-retest and internal consistency reliabilities.