In remembrance of Dennis L. Hart, PT, PhD.

J Orthop Sports Phys Ther 2012;42(6):489-490. doi:10.2519/jospt.2012.0109

STUDY DESIGN: Retrospective analysis of longitudinal, observational cohort data. OBJECTIVES: To compare discriminating ability and minimal clinically important improvement (MCII) calculated using functional status (FS) measures estimated from the lumbar computerized adaptive test (LCAT) and Modified Oswestry Low Back Pain Disability Questionnaire (ODQ). BACKGROUND: The LCAT and ODQ are commonly used to estimate FS in patients seeking outpatient therapy but have not been compared directly. METHODS: Data from 8198 adult patients who completed the LCAT and ODQ at intake were analyzed, 3379 (41%) of whom completed both surveys at discharge. Global ratings of change data were available for 980 patients. Discriminating ability of FS estimates from the LCAT and ODQ was estimated using relative validity, calculated by dividing F values from LCAT and ODQ analyses of covariance for important risk-adjustment variables. MCII was estimated using receiver-operating-characteristic analyses by quartiles of intake FS values, and areas under the curves were compared. RESULTS: Relative validity ratios favored the LCAT for age (3.7; 95% confidence interval [CI]: 2.0, 8.9), acuity (1.3; 95% CI: 1.1, 1.6), comorbidities (1.8; 95% CI: 1.3, 2.6), and surgical history (1.8; 95% CI: 1.2, 2.9). MCII cut scores per quartile favored the LCAT. Receiver-operating-characteristic areas under the curves were not different. CONCLUSION: FS measures estimated by both questionnaires had similar psychometric characteristics. The LCAT FS estimates tended to be more discriminating than ODQ FS estimates. MCII cut scores by quartile of intake FS favored the LCAT. Given the need to be efficient and precise in estimating measures of FS, particularly in older patients, results favor the LCAT in busy, automated outpatient therapy clinics, which are increasingly serving an aging population.

J Orthop Sports Phys Ther 2012;42(6):541-551, Epub 19 April 2012. doi:10.2519/jospt.2012.3942

KEY WORDS: computerized adaptive testing, lumbar spine, minimal clinically important difference, Oswestry, relative validity

STUDY DESIGN: Prospective, longitudinal, observational cohort design. OBJECTIVE: The primary aim was to examine the association between changes in psychosocial distress (PD), and functional status (FS) and pain intensity at discharge from physical therapy. BACKGROUND: Patients with lumbar impairments seeking physical therapy commonly demonstrate elevated PD. However, it is not clear if PD changes that occur during physical therapy management are associated with improved clinical outcomes. METHODS: Data from adults (n = 692) with lumbar impairment were analyzed. Patients were screened using the Symptom Checklist Back Pain Prediction Model questionnaire (SCL BPPM) to identify patients at intake and discharge into 3 levels of risk for persistent disability (high, intermediate, or low). SCL BPPM classifications allowed for 5 patterns of change in PD during therapy (decreased, stable low, stable intermediate, stable high, or increased). Associations between PD change patterns and discharge FS and pain intensity were assessed using multivariable linear regression models, controlling for selected risk-adjustment variables. RESULTS: Proportions of patients classified by patterns of PD change for decreased, stable low, stable intermediate, stable high, and increased were 0.34, 0.52, 0.05, 0.06, and 0.03, respectively. Compared to the decreased PD group, (1) increased, stable high, and stable intermediate PD patterns were associated with worse discharge FS scores (–7.9 [95% CI: –13.5, –2.21], –10.9 [95% CI: –15.25, –6.49], and –8.9 [95% CI: –13.65, –4.21] units, respectively), and (2) stable high and stable intermediate PD patterns were associated with higher pain intensity (2.59 [95% CI: 1.81, 3.56] and 2.14 [95% CI: 1.25, 3.04] units, respectively). CONCLUSIONS: Lower FS and higher pain intensity outcomes were associated in similar but not identical patterns with patients whose SCL BPPM classification of PD increased, or remained at high or intermediate levels during physical therapy. Serial assessments of change in PD during rehabilitation are recommended as a possible treatment-monitoring tool.

J Orthop Sports Phys Ther 2011;41(12):969-980. doi:10.2519/jospt.2011.3814

KEY WORDS: computerized adaptive testing, depression, functional and pain outcomes, lumbar spine, psychosocial distress, somatization

STUDY DESIGN: Retrospective analysis of a prospective, longitudinal cohort study of 30 858 patients being treated for a lumbar spine dysfunction in outpatient physical therapy. OBJECTIVES: To determine effect of adding a single-item screening variable classifying patients with elevated versus not-elevated scores of fear-avoidance beliefs of physical activities at intake, on a model predicting risk-adjusted functional status (FS) outcomes. BACKGROUND: Outcomes must be risk-adjusted before making meaningful interpretations. Elevated fear-avoidance beliefs scores have been predictive of poor outcomes. But the importance of elevated fear-avoidance scores in a multivariable model predicting FS outcomes needs further study. METHODS: Using retrospective analyses, predictive ability (R²) of multivariable linear regression models of discharge FS with and without classification by elevated versus not-elevated fear-avoidance scores were compared, while controlling for intake FS, age, symptom acuity, surgical history, gender, number of comorbidities, and payer. Percent variance controlled and beta coefficients (95% confidence intervals) of each variable in both models were compared. A split-half design was used for model cross-validation. Predictive ratios (predicted FS, divided by actual discharge FS) were assessed. RESULTS: Adding fear-avoidance beliefs classification to the discharge FS model improved (P<.001) model predictive ability but only slightly (R² without, and with, fear-avoidance classification, 0.2997 and 0.3010, respectively). Variables impacted models similarly (95% confidence intervals not different). Fear-avoidance classification added 0.2% data variance control to the existing model. Cross-validation was supported. Predictive ratios were 1.09 and 1.10, without and with fear-avoidance, respectively. CONCLUSION: Although screening for elevated fear-avoidance beliefs of physical activities significantly improves the FS outcomes predictive model, the amount of additional meaningful interpretation of FS outcomes was minimal. Exploration of other clinically relevant variables designed to improve outcomes prediction is warranted. LEVEL OF EVIDENCE: Prognosis, level 2c.

J Orthop Sports Phys Ther 2011;41(5):336-345, Epub 6 April 2011. doi:10.2519/jospt.2011.3534

KEY WORDS: computerized adaptive testing, outpatient rehabilitation, patient demographics, prediction models