Pain Drawing and psychological distress in low back pain - Systematic Review and Meta-analysis.

Background and Objective: Although pain drawings (PDs) are commonly used to identify pain site and extent, their value in recognizing psychological distress in low back pain (LBP) has also been advocated. The aim of this systematic review and meta-analysis was to estimate the accuracy of qualitative PDs in identifying psychological distress in subacute and chronic LBP patients. This review expanded upon previous studies explicitly targeting the population of interest, and focusing on specific characteristics of outcome measures. Materials and Methods: Data were obtained from PubMed, EBSCO, Scopus, PsycINFO and ISI Web of Science from their inception to July 2014. Additional records were searched through other sources to complement the databases findings. All diagnostic studies investigating the correlation between PDs by Ransford or Udén and psychological distress were considered. Two reviewers independently selected the studies and extracted the results. Quality assessment of bias and applicability was conducted using the Quality of Diagnostic Accuracy Studies-2 (QUADAS-2). Measures of diagnostic accuracy were pooled using a random effects model. Results: Seven studies enrolling 1,622 patients were included. The summary estimates were: sensitivity=0.45 (95% CI 0.34, 0.61), specificity=0.66 (95% CI 0.53, 0.82), positive likelihood ratio=1.23 (95% CI 0.93, 1.62), negative likelihood ratio=0.84 (95% CI 0.70, 1.01), and diagnostic odds ratio=1.46 (95% CI 0.79, 2.68). The area under the curve was 78% (CI, 57% to 99%). Overall, the quality of the studies measured with QUADAS-2 was poor to moderate. Discussion: The summaries of sensitivity and specificity, the LR+ and LR- values as well as the large range of the results do not allow us to confirm the discriminative power of PDs without reservation. Moreover, the area under the ROC curve suggests that there is only modest validity in using PDs to detect anxiety, depression or illness behaviour in LBP patients. Furthermore, all of the data were drawn from poor to moderate quality studies. Conclusion: The results of this systematic review did not show any substantial support for the accuracy of PDs in detecting psychological distress in subacute and chronic LBP. The limited number and quality of studies do not permit us to draw any final conclusions.