1. Research Methods in Health;Bowling,1997
2. Survey Methods in Community Medicine;Abramson,1999
3. Cardiff Software Inc., Teleform Standard User Guide Version 6.1, San Marcos, 1998.
4. A brief screening tool for knee pain in primary care. 1. Validity and reliability;Jinks;Rheumatology,2001
5. SF 36 Health Survey. Manual and Interpretation Guide;Ware,1993