The 14-item Paediatric Throat Disorders Outcome Test: a valid, sensitive, reliable, parent-reported outcome measure for paediatric throat disorders

Objectives: We modified and abbreviated a pre-existing research questionnaire, the Tonsil and Adenoid Health Status Instrument, to make it suitable for rapid completion as a disease-specific, health-related quality of life research tool for children with tonsil and adenoid disease in the UK. We determined the main psychometric properties of the resulting 14-item Paediatric Throat Disorders Outcome Test. Design, setting and participants: Pre- and post-operative questionnaires were completed by the parents of children with throat disorders referred to two large hospitals. We included children with recurrent tonsillitis and with obstructive sleep apnoea. A separate cohort of healthy children of comparable age range was also studied. Main outcome measures: The test's internal consistency and responsiveness were analysed and its construct validity documented via known-group differences. Results: A total of 126 completed questionnaires were received from the hospital referral group. The children's mean age was 6.5 years (range one to 16). The 40 unaffected children were well matched in age to the study population (mean 6.1 years, range two to 15). Cronbach's a coefficient for the pre-operative assessment total score was 0.84. The test retest reliability coefficient for the total score was 0.98, indicating very high reproducibility. The 14-item Paediatric Throat Disorders Outcome Test discriminated well between children known to suffer with throat problems and a group of healthy controls (p < 0.0001; t = 24.016). Six months after surgical intervention, parentally reported questionnaire scores had improved (i.e. were lower) (p < 0.0001; t = 7.01). The standard effect size (i.e. change in mean divided by baseline standard deviation) for children for whom post-operative questionnaires were completed was 1.53; this is very large. Conclusions: The 14-item Paediatric Throat Disorders Outcome Test is an appropriate, disease-specific, parent-reported outcome measure for children with throat disorders, for which we have demonstrated internal consistency, reliability, responsiveness to change and two forms of construct validity.