The psychometric profile of chiropractic patients in Norway and England: using and comparing the generic versions of the STarT Back 5-item screening tool and the Bournemouth Questionnaire

BACKGROUND Musculoskeletal pain and low back pain (LBP) in particular is one of the more costly health challenges to society. The STarT Back Tool (SBT) has been developed in the UK with a view to identifying subgroups of LBP patients in order to guide more cost effective care decisions. The Bournemouth Questionnaire (BQ) is a validated multidimensional patient reported outcome measure (PROM) that is widely used in routine clinical practice settings. This study sets out to describe and compare SBT and BQ scores within and between populations of patients presenting for chiropractic care in Norway and Great Britain. METHODS Patient demographics, BQ and the 5-item generic condition SBT data were collected from patients presenting with musculoskeletal pain to 18 Norwegian and 12 English chiropractors. Analysis of correlation between groups was achieved using a 1-way Chi2 approximation (p < 0.05). RESULTS Eleven percent of Norwegian LBP patients (n = 214) and 24% of English LBP patients (n = 186) were "distressed by their condition" (SBT > 4). By comparison, Norwegian chiropractic patients are: somewhat younger, have lower BQ scores, are less distressed by the condition and score significantly lower on items relating to catastrophisation and depression than English patients. There was an apparent association between total BQ and SBT scores (correlation 0.59, p < .0001) and patients who scored higher than 45 (IQR 39-58) on BQ were more likely to respond "distressed by condition" (>4) on SBT. Furthermore, patients in "distressed by condition" SBT category who had marked the "low mood" question on SBT also had a high score on the "depression" question of BQ (>6 (IQR 4-8), correlation 0.54, p < .0001). CONCLUSION The BQ and SBT appear to identify the same subgroups in some, but not all of the measured items. It appears that unknown factors result in variations between patients seeking chiropractic care for comparable complaints in primary care in England vs Norway. Comparison of populations from Norway and UK demonstrate that extrapolating and pooling of data in relation to different populations should be done with caution, in regard to these stratification tools.