Can we assess baseline pain and global health retrospectively?
OBJECTIVE
To study the agreement between patients' actual baseline assessments of pain and global health before treatment and retrospective assessments collected 2 weeks after treatment.


METHODS
Data were collected in a prospective study of 200 rheumatology outpatients treated with a local corticosteroid injection. At baseline and 2-week follow-up, localized pain and global health were assessed on 100 mm visual analogue scales. The follow-up questionnaire was extended with a retrospective assessment of pain and global health before treatment.


RESULTS
At follow-up patients slightly overestimated the severity of pain and global health before treatment. Actual and retrospective assessments were adequately correlated (pain: r(r(r(s) = 0.73; global health: r(s) = 0.67). Bland-Altman analysis showed that both pain and global health were characterized by high intra-individual variation between actual and retrospective assessments, with the 95% limits of agreement (-37.3 to 32.3 mm for pain and -49.7 to 37.8 mm for global health) far exceeding proposed values for minimal clinically important differences.


CONCLUSIONS
Over a 2-week interval, patients' retrospective assessments of baseline pain and global health are fairly accurate and adequately correlated with actual baseline scores. At the group level, retrospective assessments can provide acceptable data on baseline pain and global health. The wide variability between actual and retrospective assessments, however, indicates that even over short time intervals there is poor individual agreement between the two methods.
ten Klooster
P M
PM
Institute for Behavioural Research, Faculty of Behavioural Sciences, University of Twente, Enschede, The Netherlands. p.m.tenklooster@utwente.nl
Drossaers-Bakker
K W
KW
Taal
E
E
van de Laar
M A F J
MA
D000305:Adrenal Cortex Hormones / Q000627:therapeutic use; D000368:Aged; D018501:Antirheumatic Agents / Q000627:therapeutic use; D003625:Data Collection; D005260:Female; D006304:Health Status; D006801:Humans; D008297:Male; D011939:Mental Recall; D008875:Middle Aged; D010146:Pain / Q000209:etiology; D010147:Pain Measurement; D011446:Prospective Studies; D015203:Reproducibility of Results; D012189:Retrospective Studies; D012216:Rheumatic Diseases / Q000150:complications / Q000188:drug therapy / Q000503:physiopathology*; D012720:Severity of Illness Index
D000305:Adrenal Cortex Hormones; D018501:Antirheumatic Agents