Rintala et al. 2004;
USA
Downs & Black = 18
Longitudinal
N = 96

Population: 69 males and 27 females; Phase I:  Male mean age  40.5 + 12.5 (23 – 70 yrs); mean YPI 11.1 + 8.8; Female mean age
37.0 + 10.8 (21 – 61 yrs); mean YPI 10.4 + 7.2 yrs
Methodology:  Assessed the consistency of pain at three (women) and four (men) measurement points across 10 years
Outcome Measures: Self-report pain characteristics

1. Of the 96 participants, approximately half the males and three-quarters of females reported consistent pain across all measurement points.

Siddall et al. 2003;
Australia
Downs & Black = 18
Longitudinal
N = 73

Population: 60 males and 13 females; mean age at baseline 40 (21 - 81 yrs); mean time post-injury at baseline < 6 mos
Methodology:  Assessed the prevalence, onset, and severity of pain
Outcome Measures: Pain intensity via numeric scale; Psychological distress; Von Korff chronic pain disability to assess pain interference on daily activities; assessed at less than 1 YPI and again at 5 YPI

1. Persons with neuropathic pain early following injury were likely to continue to experience ongoing and severe pain.

Putzke et al. 2002a;
USA
Downs & Black = 17
Longitudinal
N = 270

Population : 210 males and 60 females; mean age at 1 YPI 36.8 + 14.3 yrs
Methodology : Examined factors that contribute to pain interference
Outcome Measures : Short-form 12, at 1 and 2 YPI

1. Age effect for pain interference was detected (p < 0.001). Youngest group with SCI who reported no pain interference at both year 1 and year 2, and the oldest group being those reporting pain interference at both year 1 and year 2.

Jensen et al. 2005;
USA
Downs & Black = 14
Longitudinal
N = 147

Population: 110 males and 37 females; mean age at follow-up 48.8 + 13.0 (21 - 88 yrs); mean YPI at follow-up 16.6 + 10.4 (3.2 - 57.4 yrs)
Methodology:  Examine the change in the prevalence and intensity of pain over time (range 2 - 6 yrs between assessments
Outcome Measures: Brief Pain Inventory Interference scale; Bodily Pain scale; SF-36; Mental Health scale

1. Overall, the change or intensity in the prevalence of pain over time was not significant.