Two fifths of the sample reported having three or more years since the start of their back pain; of these, 40% reported having their pain for over 10 years. Among people with less than 3 years of pain, a third (33.5%) reported that their pain had started in the previous 3 months. All baseline prognostic indicators were present in over a fifth of the sample. At 12-months, 6.7%

were pain free (CPG 0), 60.9% were in CPG I–II, 14.7% in CPG III and 17.7% of the sample had a poor outcome (CPG IV). Table 2 presents the associations between potential baseline prognostic indicators and 12-month outcome. In unadjusted analyses, 17 baseline factors were significantly associated with highly disabling and severely limiting pain at follow-up. Not GSK1349572 molecular weight being in employment, work absence, high pain intensity or functional disability, bothersomeness and poor self-rated health indicated the strongest risk of a poor prognosis, all had statistically significant crude RRs above five. After adjustment for potential confounders, statistically significant associations remained for seven baseline factors: not being in employment, work absence, long episode duration, high

functional disability, high pain intensity, anxiety and poor self-rated health. The strongest associations with outcome were found for not being in employment (RR 4.2; 95% CI 2.0, 8.5) and high pain intensity (RR 4.1; 95% CI 1.7, 9.9). The proportion of persistent Selleck LY294002 problems at 12 months associated with each factor, calculated using PAFs, is shown in Table 3. All proportions fell after adjustment, but many of the adjusted figures were high: five prognostic indicators had statistically significant proportions, and six were above 40%. The highest proportion was for high pain intensity, indicating that in 68% of LBP patients with a poor outcome, outcome is related to high baseline pain intensity, regardless of the presence of the other risk factors. The next highest proportion was for not being in employment (64%).

Poor self-rated health, and high functional disability, upper body pain and pain bothersomeness all also had proportions over 40% (although non-significant for upper body pain and bothersomeness). Combining risk factors medroxyprogesterone within domains showed that symptom severity had the highest cumulative effect (Table 4); people with both high pain and high functional disability comprised 72% of everyone with a poor outcome and were almost seven times more likely (RR 6.9) to have a poor outcome than people with neither high pain nor high disability. The cumulative proportion was 74% for the symptom severity domain, indicating that in almost three quarters of people with a poor outcome, that outcome is related to baseline symptom severity. Widespreadness of pain had a cumulative proportion of 70%. Pain affect had a lower cumulative proportion of 40% with pain cognition having a small effect (13%) on outcome.