Background The Photograph Series of Daily Activities-short electronic version (PHODA-SeV) assesses perceived harmfulness of daily activities in patients with low back pain (LBP). Although there is some evidence that the PHODA-SeV is a reliable and valid tool, its psychometric properties have not been fully investigated. Objectives To investigate the test-retest reliability, measurement error, interpretability, construct validity, and internal and external responsiveness of the PHODA-SeV in patients with chronic LBP. Methods Ninety-one patients were included in the analysis for this prospective cohort study. For reliability purposes, the PHODA-SeV was administered twice, with a 1-week interval before beginning treatment. Pain, disability, and measures of pain-related fear (ie, PHODA-SeV, Fear-Avoidance Beliefs Questionnaire [FABQ], and Tampa Scale of Kinesiophobia [TSK]) were collected before and after the 8-week treatment period. Results The PHODA-SeV showed excellent reliability (intraclass correlation coefficient model 2,1 = 0.91), without evidence of ceiling and floor effects. The construct validity analysis demonstrated fair correlations (r = 0.25-0.50) of the PHODA-SeV with the FABQ, but no correlation with the TSK (r<0.25). For internal responsiveness, the PHODA-SeV showed an effect size of 0.87 and a standardized response mean of 0.92, interpreted as a large effect (greater than 0.80). For external responsiveness, the correlations between the PHODA-SeV and changes in the TSK and FABQ were considered low, and the receiver operating characteristic curve analyses revealed an area under the curve lower than the proposed threshold of 0.70. Conclusion The PHODA-SeV is a reliable tool that can detect changes over time in pain-related fear in patients with chronic LBP undergoing physical therapy treatment. This tool, however, failed to identify those patients who did or did not improve, according to other pain-related fear measures. J Orthop Sports Phys Ther 2018;48(9):719-727. Epub 23 May 2018. doi:10.2519/jospt.2018.7864.

Background Physical overload at work has been described as a risk factor for the development of low back pain. However, few studies have investigated the prognostic value of perceived physical overload at work in patients with chronic low back pain. Objective To investigate the association of perceived physical overload at work with pain and disability over a period of 6 months in patients with chronic non-specific low back pain. Methods Patients with chronic LBP seeking physiotherapy care were considered eligible. Clinical data collected were: pain intensity, disability, fear of movement, depression and perceived physical overload at work. Linear regression analyses were used to investigate the association of perceived physical workload at work at baseline with pain intensity and disability at 6-month follow-up. The total score and the score for each category of the physical overload at work questionnaire were analyzed separately. Results Ninety-two patients with chronic low back pain were included in the analysis. The subcategories of the physical overload questionnaire were not significantly associated with pain intensity at 6-month follow-up. However, age, disability at baseline and perceived physical overload related to postures of the trunk (B = −0.60 95% CI − 1.18 to − 0.02) and related to positions of the arms (B = 2.72 95% CI 0.07 to 5.37) were significantly associated with disability at 6-month follow-up. Conclusion Although perceived physical overload at work was not associated with pain intensity in patients with chronic LBP at 6-month follow-up, we identified a significant association between perceived physical overload related to postures of the trunk and positions of the arms with disability at 6-month follow-up.