Purpose: The relative's questionnaire (RQ) was developed to assess outcome after brain injury. The present study investigated its test-retest reliability when used in a postal survey.
Method: Hospital records were used to identify and contact 288 surviving patients treated for brain injury five to seven years earlier. Patients were sent a copy of the RQ (RQ1) and one month later a second copy (RQ2) was sent to those who returned RQ1.
Result: Two hundred and eleven patients were successfully contacted, of whom 128 (61%) returned RQ1, and 94 of these (73%) returned RQ2. The reliability of items was variable, with most having a kappa value of > 0.6 suggesting 'substantial agreement' or better.
Conclusion: The data presented suggest that the RQ is a reliable instrument in collecting outcome information in brain-injured patients by postal survey. Further research is recommended to test the suitability of the RQ for the use as a telephone interview.