[Development and validation of the Stapesplasty Outcome Test 25 (SPOT-25)].

BACKGROUND: Otosclerosis affects health-related quality of life (HRQOL). Until now, measurements have only been performed using audiometric data or non-validated quality of life questionnaires.

OBJECTIVE: The objective of this study was to develop the first validated disease-specific HRQOL measuring instrument to determine HRQOL in otosclerosis.

MATERIALS AND METHODS: After sequential analysis and item reduction of the initial Stapesplasty Outcome Test 47 (SPOT-47), the SPOT-25 was validated prospectively on 52 otosclerosis patients undergoing stapes surgery. In addition to the overall score, four subscores were defined (hearing function, tinnitus, social restrictions, mental condition).

RESULTS: The SPOT-25 showed a high internal consistency (Cronbach's α > 0.7), allowed discrimination between otosclerosis patients and healthy subjects, and demonstrated acceptable test-retest reliability (r = 0.85). After stapes surgery, the HRQOL improved significantly. The responsiveness was high.

CONCLUSION: The SPOT-25 is the first validated disease-specific instrument for HRQOL measurement in otosclerosis patients. It should be used routinely for quality control.