The patient-specific functional scale: psychometrics, clinimetrics, and application as a clinical outcome measure.
METHODS
Systematic review of the literature.


OBJECTIVE
To summarize peer-reviewed literature on the reliability, validity, and responsiveness of the Patient-Specific Functional Scale (PSFS), and to identify its use as an outcome measure.


METHODS
Searches were performed of several electronic databases from 1995 to May 2010. Studies included were published articles containing (1) primary research investigating the psychometric and clinimetrics of the PSFS or (2) the implementation of the PSFS as an outcome measure. We assessed the methodological quality of studies included in the first category.


RESULTS
Two hundred forty-two articles published from 1994 to May 2010 were identified. Of these, 66 met the inclusion criteria for this review, with 13 reporting the measurement properties of the PSFS, 55 implementing the PSFS as an outcome measure, and 2 doing both of the above. The PSFS was reported to be valid, reliable, and responsive in populations with knee dysfunction, cervical radiculopathy, acute low back pain, mechanical low back pain, and neck dysfunction. The PSFS was found to be reliable and responsive in populations with chronic low back pain. The PSFS was also reported to be valid, reliable, or responsive in individuals with a limited number of acute, subacute, and chronic conditions. This review found that the PSFS is also being used as an outcome measure in many other conditions, despite a lack of published evidence supporting its validity in these conditions.


CONCLUSIONS
Although the use of the PSFS as an outcome measure is increasing in physiotherapy practice, there are gaps in the research literature regarding its validity, reliability, and responsiveness in many health conditions.
School of Physiotherapy, University of Otago, New Zealand.
Katyana Kowalchuk
KK
Horn
Sophie
S
Jennings
Gillian
G
Richardson
Ditte Van
DV
Vliet
Cheryl
C
Hefford
J Haxby
JH
Abbott
D016208:Databases, Factual; D004185:Disability Evaluation; D006305:Health Status Indicators; D006801:Humans; D017116:Low Back Pain / Q000534:rehabilitation; D009140:Musculoskeletal Diseases / Q000523:psychology / Q000534:rehabilitation*; D011594:Psychometrics / Q000295:instrumentation* / Q000379:methods; D012372:ROC Curve; D015203:Reproducibility of Results; D011795:Surveys and Questionnaires; D016896:Treatment Outcome