Validation of the howRu and howRwe questionnaires at the individual patient level

Steven H. Hendriks, Jojanneke Rutgers, Peter R. van Dijk, Klaas H. Groenier, Henk J. G. Bilo, Nanne Kleefstra, Janwillem W. H. Kocks, Kornelis J. J. van Hateren, Marco H. Blanker

The howRu and howRwe are new short questionnaires which are meant to measure health-related quality of life and patient experience. However, validation at the individual patient level has not yet taken place. We aimed to investigate the validity of both questionnaires at the individual patient level. In this prospective validation study, patients were asked to complete both questionnaires and comment on their answers in a semi-structured in-depth interview. Based on the transcribed interviews, a panel of 45 general practitioners and 45 patients filled out the questionnaires as they thought the patients had completed them. The questionnaires were considered valid instruments when a reliable and acceptable level of agreement was reached between the patient's score and the score of a review panel, defined as a concordance correlation coefficient (CCC) of ≥0.70. Bland-Altman plots were also made. Ninety patients were included. The CCC of the howRu total score of the review panel and patients was 0.80 (95 % CI 0.73 to 0.86). Bland-Altman plots showed a mean difference of -0.96 and the limits of agreement ranged from -2.87 to 0.95. The CCC of the howRwe total score was 0.57 (95 % CI 0.42 to 0.69). The mean difference on the Bland-Altman plots was -0.54 and the limits of agreement ranged from -3.59 to 2.52. The howRu seems to be a valid questionnaire for measuring health-related quality of life at the individual patient level. We do not advice to use the tested version of the howRwe questionnaire for assessing patient experience at the individual patient level. The study was registered at clinicaltrials.gov NCT01830803 . Registration date: 5 April 2013.