Low back pain outcome measurement assessment in chiropractic teaching clinics: responsiveness and applicability of two functional disability questionnaires.
OBJECTIVE
The major aims were to evaluate responsiveness and clinical/research applicability of the Revised Oswestry Disability Questionnaire (ODQ) and the Dallas Pain Questionnaire (DPQ). Construct and content validity were assessed. Patient characteristics and outcomes were also documented.


METHODS
Longitudinal observational study.


METHODS
College outpatient clinics.


METHODS
Six hundred sixty-three consecutive new patients accepted for treatment of low back pain (LBP) at the clinics over a 1-yr period, age 18 or older.


METHODS
Treatment of low back pain by senior interns under the supervision of staff clinicians.


METHODS
ODQ and DPQ administered at baseline, 2 wk, 1 month, and monthly up to 6 months. Responsiveness: mean standardized change score (delta' = mudif/sigma dif), relative efficiency ([RE = delta' ODQ/delta DPQ']2), and improvement rates (IR). Applicability: instrument completion rates. Construct validity: correlation with VAS for pain intensity.


RESULTS
ODQ responsiveness was generally consistent over time (delta' = .70-.83) and negligibly better than the DPQ activities of daily living scale (RE = 1.00-1.35); most patients self-reporting improvement showed positive outcomes (IR = 97%). For large samples (n > 100): delta' = .47-.63 and IR = 81% for the DPQ work/leisure scale; delta' = .17-.40 and IR = 54% for the DPQ anxiety/depression and social dimensions. Completion rates: 65%-78% of all instruments; 81%-100% of individual scales. Construct validity: r = .44-.68 for the ODQ, DPQ activities of daily living, and DPQ work/leisure scales; r = .20-.40 for the anxiety/depression scale.


CONCLUSIONS
The ODQ and the activities of daily living and work/leisure scales from the DPQ appear appropriate for monitoring LBP patients returning for care to chiropractic teaching clinics. The social and anxiety/depression dimensions of the DPQ do not appear to be responsive in this population. The latter scale may be unsuitable on the grounds of misinterpretations.
Haas
M
M
Research Department, Western States Chiropractic College, Portland, OR 97230-3099, USA.
Jacobs
G E
GE
Raphael
R
R
Petzing
K
K
D000203:Activities of Daily Living; D000328:Adult; D000553:Ambulatory Care; D002684:Chiropractic; D004185:Disability Evaluation; D005260:Female; D006801:Humans; D008137:Longitudinal Studies; D017116:Low Back Pain / Q000628:therapy*; D008297:Male; D017063:Outcome Assessment, Health Care; D010147:Pain Measurement; D015203:Reproducibility of Results; D011795:Surveys and Questionnaires