Table 1 Overview of ten studies in which LBP trajectories have been identified by data-driven approaches
From: What have we learned from ten years of trajectory research in low back pain?
Author Setting Sample size | Design | Timing and duration of follow-up | Measurement tool | Outcome measurea | Clustering method | Identified clusters Label (% of cohort) |
|---|---|---|---|---|---|---|
Dunn Primary care General practice n = 342 (2001–03) [8] n = 155 (2009–10) [10] | Observational | Monthly for 6 months | Questionnaires | LBP Intensity 3-cat. | Latent Class Analysis | 2001-03 cohort Persistent mild 31 % Recovering 30 % Severe chronic 21 % Fluctuating 13 % 2009-10 cohort Persistent mild 37 % No or occasional 31 % Persistent severe 21 % Fluctuating 11 % |
Axen Primary care [12] Chiropractic practice n = 176 | Observational | Weekly for 6 months | Text messaging | LBP Frequency 0–7 | Hierarchical Cluster informed by spline regression (intercept, slopes, knot) | Typical [improve markedly during 4 weeks] 41 % Stable [mild] 24 % Slow improvement 15 % Fast improvement 13 % Not classified 6 % |
Kongsted Primary care [11] General practice + Chiropractic practice n = 1082 | Observational | Weekly for 12 months | Text messaging | LBP Intensity 0–10 LBP Intensity 3-cat. LBP Frequency 0–7 LBP Frequency 3-cat. | Latent Class Analysis Latent Class Growth Analysis | bMild episodic 29 % Recovery 26 % Moderate/ severe 20 % Improvement w/ relapse 13 % Slow improvement 12 % |
Macedo Primary care + Secondary care [16] General practice + outpatient clinic (≥3 months duration) n = 155 | RCT | Monthly for 12 months | Text messaging | LBP Intensity 0–10 | Hierarchical Cluster informed by linear regression (deviations from line) | Non-fluctuating 87 % recovering mild 54 % persistent moderate 58 % severe chronic 17 % Fluctuating 13 % |
Chen Workers on sick leave [13] n = 678 | Observational | Week 4, 10, 16,52 | Interview | LBP Intensity 0–10 | Hierarchical Cluster informed by linear regression (slope) | Continuous high 42 % Fluctuating 33 % Large reduction 12 % Moderate reduction 12 % Increasing 1 % |
Tamcan Population-based [14] n = 305 | Observational | Weekly for 12 months | Diary | LBP Intensity 3-cat. | Latent Class Analysis | Moderate 35 % Fluctuating 34 % Mild 20 % Severe 10 % |
Kent Secondary care [15] Outpatient clinic n = 322 | RCT | Fortnightly for 12 months Monthly for 12 months | Test messaging | LBP Frequency 0–7 | Two-step cluster | Fortnightly outcomesc Severe persistent 42 % Moderate 33 % Severe fluctuating 25 % Monthly outcomes Severe 62 % Moderate 38 % |
Deyo Primary care + emergency care [17] Age >65 years n = 3929 | Observational | Month 3, 6, 12 | Questionnaire or phone | LBP intensity 0–10 Activity limitation | Latent Class Analysis | Pain intensity Moderate – High 36 % Low – Moderate 31 % High 13 % Moderate –Recovery 7 % Severe – Recovery 7 % Low 6 % Activity limitation Moderate – High 32 % Low – Moderate 25 % Low 19 % High 19 % Recovery 6 % |
Downie Primary care [18] General practice (<6 weeks duration of LBP) N = 1585 | RCT | Week 1, 2, 4, 12 | Recorded in a booklet - transcribed by phone | LBP intensity | Latent Class Growth Analysis | Rapid recovery 36 % Recovery by week 12 34 % Incomplete recovery 14 % Fluctuating pain 11 % Persistent high pain 5 % |