Development of a measure of hypodontia patients' expectations of the process and outcome of combined orthodontic and restorative treatment.

OBJECTIVES: To devise and assess the psychometric properties of a measure that investigates hypodontia patients' expectations of the process and outcome of combined orthodontic/restorative treatment.

SETTING: Specialised secondary care facility for individuals with hypodontia.

MATERIALS AND METHODS: Mixed research design with three phases: (a) Thematic analysis of data from individual interviews with 25 hypodontia patients/16 parents to generate the questionnaire items. (b) Questionnaire design, assessment of readability and face/content validity with 10 patients. (c) Survey of 32 new hypodontia patients to determine the internal consistency of the measure.

RESULTS: Three main themes related to the treatment process emerged from the qualitative data: 'hypodontia clinic', 'orthodontic treatment' and 'restorative treatment'. Three main themes were also revealed relating to treatment outcome: 'changes in appearance', 'psychosocial changes' and 'functional changes'. A 28 item questionnaire was constructed using a mix of visual analogue scale (VAS) and categorical response format. The Flesch reading ease score of the measure was 78, equivalent to a reading age of 9-10 years. Face and content validity were good. The overall Cronbach's alpha was 0.80 while for the treatment process and treatment outcome subscales it was 0.71 and 0.88 respectively.

CONCLUSIONS: A patient-based measure of the process and outcome of combined orthodontic/restorative treatment for hypodontia patients has been developed which has good face and construct validity and satisfactory internal consistency.

CLINICAL SIGNIFICANCE: Patient expectations of treatment are important in determining not only their satisfaction with treatment outcomes but also their engagement with the clinical process. This questionnaire is a first step in operationalising the expectations of hypodontia patients through assessment tools that can then determine whether pre-treatment counselling is required and aid the consent and treatment planning process, thus improving the quality of treatment provided by approximating the expectations the patients hold to their actual experience.