Meta-analysis identifies Back Pain Questionnaire reliability influenced more by instrument than study design or population

Physical functioning following spinal cord stimulation: a systematic review and meta-analysis

BACKGROUND

Spinal cord stimulation (SCS) has emerged as an important treatment for chronic pain disorders. While there is evidence supporting improvement in pain intensity with SCS therapy, efforts to synthesize the evidence on physical functioning are lacking.

OBJECTIVE

The primary objective of this meta-analysis was to assess long-term physical function following 12 months of SCS for chronic back pain.

EVIDENCE REVIEW

PubMed, EMBASE, Scopus, and CENTRAL databases were searched for original peer-reviewed publications investigating physical function following SCS. The primary outcome was physical function at 12 months following SCS therapy for chronic back pain compared with baseline. A random effects model with an inverse variable method was used. The Grading of Recommendation, Assessment, Development, and Evaluation (GRADE) framework was used to determine the certainty of evidence.

FINDINGS

A total of 518 studies were screened, of which 36 were included. Twenty-two studies were pooled in the meta-analysis. There was a significant reduction in Oswestry Disability Index (ODI) scores at all time frames up to 24 months following implantation. Pooled results revealed significant improvement in ODI scores at 12 months with a mean difference of -17.00% (95% CI -23.07 to -10.94, p<0.001). There was a very low certainty of evidence in this finding as per the GRADE framework. There was no significant difference in subgroup analyses based on study design (randomised controlled trials (RCTs) vs non-RCTs), study funding, or stimulation type.

CONCLUSION

This meta-analysis highlights significant improvements in physical function after SCS therapy. However, this finding was limited by a very low GRADE certainty of evidence and high heterogeneity.

Construct validity and responsiveness of commonly used patient reported outcome instruments in decompression for lumbar spinal stenosis

BACKGROUND

Validity and responsiveness of Oswestry disability index (ODI), Roland Morris disability questionnaires (RMDQ), Short Form-12 Physical Component Score (SF-12 PCS) and Short Form-12 Mental Component Score (SF-12 MCS) in patients undergoing open decompression for lumbar canal stenosis has not been previously reported.

METHODS

Outcome assessment was prospectively evaluated using the ODI, RMDQ, SF-12 PCS and SF-12 MCS pre-intervention and at average follow-up of three months post-intervention. Pearson correlation coefficient was used to evaluate the association between change in values of ODI, RMDQ, SF-12 PCS and SF-12 MCS. Distribution based methods (Effect size [ES], standardised response mean [SRM]) and anchor based method (Area under the curve [AUC] of receiver operating curve [ROC]) were used to determine responsiveness. AUC value ≥ 0.70 is considered as adequate level of responsiveness and the outcome instrument with the largest AUC is considered to be the most responsive outcome instrument.

RESULTS

This study included 77 participants. Responsiveness was assessed at a mean follow-up of 12 weeks postoperatively. There was significant strong correlation between ODI and RMDQ (r = 0.65, p < 0.0001). The ES of ODI, RMDQ, SF-12 PCS and SF-12 MCS were 1.54, 1.48, 1.85 and 0.51 respectively. The SRM of RMDQ, ODI, SF-12 PCS and SF-12 MCS were 1.22, 1.17, 1.0 and 0.47 respectively. AUC of ODI, RMDQ, SF-12 PCS and SF-12 MCS were 0.83-0.88, 0.82 to 0.86, 0.78 to 0.81 and 0.69 to 0.70 respectively.

CONCLUSION

It is recommended to use either ODI or RMDQ as region specific patient reported outcome instrument and SF-12 PCS as a health related quality of life outcome instrument to evaluate outcome after decompressive laminectomy for lumbar canal stenosis.

PROMIS Physical Function Short Forms Display Item- and Scale-Level Characteristics at Least as Good as the Roland Morris Disability Questionnaire in Patients With Chronic Low Back Pain

OBJECTIVE

To compare dimensionality, item-level characteristics, scale-level reliability, and construct validity of PROMIS Physical Function short forms (PROMIS-PF) and 24-item Roland Morris Disability Questionnaire (RMDQ-24) in patients with chronic low back pain (LBP).

DESIGN

Cross-sectional study.

SETTING

Secondary care center for rehabilitation and rheumatology.

PARTICIPANTS

Patients with nonspecific LBP ≥3 months (N=768). Mean age was 49±13 years, 77% were female, and 54% displayed pain for more than 5 years.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

Dutch versions of the 4-, 6-, 8-, 10-, and 20-item PROMIS-PF and of the RMDQ-24.

RESULTS

PROMIS-PF-6, PROMIS-PF-8, and RMDQ-24 exhibited sufficient unidimensionality (confirmatory factor analysis: comparative fit index>0.950, Tucker-Lewis index>0.950, root means square error of approximation<0.060), whereas the other instruments did not. All instruments were free of local dependence except PROMIS-PF-20 with 4 item pairs with clear residual correlations. Mokken scale analysis found 1 nonmonotone item for PROMIS-PF-20 and 8 for RMDQ-24 (ie, the probability of endorsing these items was not increasing with increasing level on the underlying construct). PROMIS-PF-20 displayed 2 misfitting items (S-χ²P value>.001). Two-parameter item response theory models found 2 items with low discrimination for RMDQ-24. All other instruments had adequate fit statistics and item parameters. PROMIS-PF-20 displayed the best scale-level reliability. Construct validity was sufficient for all instruments as all hypotheses on expected correlations with other instruments and differences between relevant subgroups were met.

CONCLUSIONS

PROMIS-PF-6, PROMIS-PF-8, and RMDQ-24 exhibited better unidimensionality, whereas PROMIS-PF-4, PROMIS-PF-6, PROMIS-PF-8, and PROMIS-PF-10 showed superior item-level characteristics. PROMIS-PF-20 was the instrument with the best scale-level reliability. This study warrants assessment of other measurement properties of PROMIS-PF short forms in comparison with disease-specific physical functioning instruments in LBP.

Choosing the right outcome measurement instruments for patients with low back pain

Choosing the most fit-for-purpose outcome measurement instruments is fundamental because using inappropriate instruments can lead to detection bias and measurement inconsistency. Recent recommendations, consensus procedures and systematic reviews on existing patient-reported outcome measures (PROMs) informed this manuscript, which provides suggestions on which outcome domains and measurement instruments to use in patients with low back pain (LBP). Six domains are identified as highly relevant: (1) physical functioning, (2) pain intensity, (3) health-related quality of life, (4) work, (5) psychological functioning and (6) pain interference. For each domain, one or more PROMs are suggested for clinical research and practice, selecting among those that are most frequently used and recommended, and that have satisfactory measurement properties in patients with LBP. Further research on the measurement properties of these suggested PROMs is needed while also considering other emerging instruments, such as the PROMIS computerised adaptive testing and short forms.

Roland-Morris Disability Questionnaire and Oswestry Disability Index: Which Has Better Measurement Properties for Measuring Physical Functioning in Nonspecific Low Back Pain? Systematic Review and Meta-Analysis

BACKGROUND

Physical functioning is a core outcome domain to be measured in nonspecific low back pain (NSLBP). A panel of experts recommended the Roland-Morris Disability Questionnaire (RMDQ) and Oswestry Disability Index (ODI) to measure this domain. The original 24-item RMDQ and ODI 2.1a are recommended by their developers.

PURPOSE

The purpose of this study was to evaluate whether the 24-item RMDQ or the ODI 2.1a has better measurement properties than the other to measure physical functioning in adult patients with NSLBP.

DATA SOURCES

Bibliographic databases (MEDLINE, Embase, CINAHL, SportDiscus, PsycINFO, and Google Scholar), references of existing reviews, and citation tracking were the data sources.

STUDY SELECTION

Two reviewers selected studies performing a head-to-head comparison of measurement properties (reliability, validity, and responsiveness) of the 2 questionnaires. The COnsensus-based Standards for the selection of health Measurement INstruments (COSMIN) checklist was used to assess the methodological quality of these studies.

DATA EXTRACTION

The studies' characteristics and results were extracted by 2 reviewers. A meta-analysis was conducted when there was sufficient clinical and methodological homogeneity among studies.

DATA SYNTHESIS

Nine articles were included, for a total of 11 studies assessing 5 measurement properties. All studies were classified as having poor or fair methodological quality. The ODI displayed better test-retest reliability and smaller measurement error, whereas the RMDQ presented better construct validity as a measure of physical functioning. There was conflicting evidence for both instruments regarding responsiveness and inconclusive evidence for internal consistency.

LIMITATIONS

The results of this review are not generalizable to all available versions of these questionnaires or to patients with specific causes for their LBP.

CONCLUSIONS

Based on existing head-to-head comparison studies, there are no strong reasons to prefer 1 of these 2 instruments to measure physical functioning in patients with NSLBP, but studies of higher quality are needed to confirm this conclusion. Foremost, content, structural, and cross-cultural validity of these questionnaires in patients with NSLBP should be assessed and compared.

Feasibility of using the patient-reported outcomes measurement information system in academic health centers: case series design on pain reduction after chiropractic care

OBJECTIVE

The purpose of this study was to test the utility of Patient-Reported Outcomes Measurement Information System (PROMIS) as a resource for collecting data on patient-reported outcomes (PRO) within academic health centers at a chiropractic college; and, to describe changes in PRO following pragmatic chiropractic care incorporating instrument-assisted soft tissue mobilization (IASTM) on pain symptoms.

METHODS

This was a pre-post intervention design without a control group (case series) involving 25 patients (14 females and 11 males; 40.5 ± 16.39 years, range 20-70 years) who completed their chiropractic care and their baseline and post-treatment pain assessments. The pragmatic chiropractic care intervention included both spinal manipulation and IASTM to treat pain symptoms. PRO's were collected using PROMIS to measure pain behavior, pain interference and pain intensity.

RESULTS

The average pre-post assessment interval was 33 ± 22.5 days (95% CI, 23-42 days). The durations of treatments ranged from one week to 10 weeks. The median number of IASTM treatments was six. Pre-post decreases in T-scores for pain behavior and pain interference were 55.5 to 48.4 and 57.7 to 48.4, respectively (P < .05). Only 12 patients had a baseline T-score for pain intensity greater than 50. The pre-post decrease in pain intensity T-scores for these 12 patients was from 53.4 to 40.9.

CONCLUSION

Within the limitations of a case series design, these data provide initial evidence on the utility of PROMIS instruments for clinical and research outcomes in chiropractic patients.