WHHQ Research
Qualitative methods
A conceptual framework of CST outcomes was developed and evaluated by CST patients and practitioners. The conceptual framework of CST outcomes became the basis from which the Warwick Holistic Health Questionnaire was developed. An introduction to the Conceptual framework can be found here: Introduction to conceptual framework of CST outcomes and a visual representation can be seen here: Diagram of Conceptual Framework of CST Outcomes. During the months of August/September 2015, a questionnaire was designed, 73 items were generated and evaluated using interviews with patients and a consensus meeting with practitioners: The 73 item list can be found here: Content of the interviews and consensus meeting with practitioners' discussions included the name of the questionnaire; design; layout; instructions; items on the questionnaire; comprehensibility of each item; appropriateness of the response options and the recall period. The questionnaire was refined based on the feedback given.
Quantitative methods
Data collection using a draft version of the 52 item WHHQ was carried out during the months of November/December 2015. The n = 142 completed questionnaires were analysed.
Exploratory factor analysis (EFA) was undertaken to identify redundant items and to assess structural validity. The questionnaire was refined based on these findings 19 items remained. Face and content validity were assessed, and the qualitative data was revisited to ensure that the items important to patients and practitioners were included; 6 items were reinstated based on this principle resulting in a 25-item questionnaire.
EFA on the WHHQ-25 pointed to a need to reduce the scale again to 18 items. Data collected on these 18 items were extracted from the WHHQ-25 for further validation. EFA showed four correlated sub-scales including self-awareness, engaging in life, taking responsibility for self, and role satisfaction.
Measurement Properties - 18 item WHHQ
The 18-item WHHQ was evaluated with a different sample of n=146 (CST n =105; cranial-osteopathy n=41) . The data followed an approximated normal distribution making it possible to apply parametric analysis. No edge effects were detected.
Reliability: Cronbach's alpha: 0.85.
Test-re-test reliability:
Test re-test reliability was evaluated on a student sample of n=109, 52 (48%) were male, 37 (34%) were between the ages of 25 to 30-year olds and 27% were between the ages of 18 to 25-years. Paired t-test suggested no difference (t=0.355, p=0.752) between mean scores at time 1 (mean: 64.21; SD:10.70) and time 2 (mean: 63.97; SD: 12.65). The ICC (0.822) exceeded the target value of 0.7. This shows that the scores stayed the same when no change in the health status had occurred suggesting that the WHHQ is repeatable.
Convergent Validity: Three comparator measures the Warwick-Edinburgh-Mental-Wellbeing-Scale [2]; the Short-Form 12 [3] and the Harry Edwards Healing Impact Questionnaire [4] were used to evaluate convergent validity. Results:
There was a strong positive correlation between WHHQ-18 and both WEMWBS and HEHIQ as hypothesized. There was no significant correlation between the WHHQ-18 and SF-12v2 PCS and MCS scales as shown in the table below.
Convergent Validity using Three Comparator Measures
|
|
Correlation with WHHQ 18 (n=105) |
2 tailed significance t-test |
|
WEMWBS (n=96) |
0.733 |
Strong positive correlation |
|
HEHIQ (n=105) |
0.811 |
Strong positive correlation |
|
SF-12 v2 (n=105) Physical Component Summary Mental Component Summary |
0.082 0.080 |
No correlation No correlation |
Responsiveness was evaluated to see whether the WHHQ detects important changes that are meaningful to clients and clinicians at individual level and a statistically significant change at group level. Distributional methods were used to evaluate responsiveness.
Individual level: For a measure to be responsive at individual level, more than 2.5% of the sample should have an increase and decrease of their change score more than 2.77*SEM. The scores increased or decreased 17% (n=25) and 4% (n=6) respectively. Scores of 46% of participants improved with Cohen D [5] effect size > 0.5 showing a moderate effect size. The standard error of measurement was 3.7.
Group level: Responsiveness measures at group level include effect size and the Standardized Response Mean value was used to calculate the P value (probability of change). Pre intervention mean score = 44.7 (SD=9.80) and post intervention = 49.0 (SD=9.13) (paired t-test t=6.15, p<0.001) with a small effect size (Cohen’s D) of 0.45. The probability of change of SRM was 0.6950 (95% CI 0.337-0.682) which is within the range (0.5-1) showing a statistically significant change.
The results indicate that the WHHQ is psychometrically sound, repeatable and responsive at both group and individual level.
References
[1] FDA, (2009), US Food & Drug administration. Patient-Reported Outcome Measures: Use in medical product development to support labeling claims.
[2] Tennant, R., Hiller, L., Fishwick, R., Platt, S., Joseph, S., Weich, S., Parkinson, J., Secker, J. & Stewart-Brown, S. (2007) The Warwick-Edinburgh Mental Well-being Scale (WEMWBS): development and UK validation. Health Qual Life Outcomes, 5
[3] Ware, J. E., Kosinski, M. & Keller, S. D. (1995) SF-12: How to score the SF-12 physical and mental health summary scales (2nd ed.). Boston, MA:
[4] Bishop, F. L., Barlow, F., Walker, J., McDermott, C. & Lewith, G. T. (2010) The Development and Validation of an outcome measure for spiritual healing: A mixed method study. Psychotherapy and Psychosomatics, 253 1- 13.
[5] Cohen, J. (1988) Statistical power analysis for the behavioral sciences . Hilsdale. NJ: Lawrence Earlbaum Associates, 2
Development Team: Dr Nicola Brough developed and validated the WHHQ for her PhD with Professor Sarah Stewart-Brown and Dr Helen Parsons of Warwick Medical School, Health Sciences Division. Nicola won the 2018 Complementary Therapy Awards Federation of Holistic Therapy Research Award for her work on the WHHQ.