Table 3.
Secondary Outcomes for the Patient Education and Placebo Patient Education Groups at 1 Week and 3, 6, and 12 Monthsa
Variable Patient Education Placebo Patient Education Effect Measure Mean Difference or OR (95% CI) P Value Chronic low back pain at 3 mo, No./total No. (%)b 33/96 (34.4) 42/93 (45.1) 0.63 (0.32 to 1.14) .13 Disabilityc 1 wk 5.6 (5.2) 7.1 (5.8) −1.6 (−3.1 to −0.1) .03 3 mo 3.5 (4.6) 4.9 (6.0) −1.7 (−3.2 to −0.2) .03 6 mo 3.8 (5.2) 4.3 (5.2) −0.8 (−2.4 to 0.7) .28 12 mo 3.0 (4.7) 3.8 (5.1) −0.8 (−2.4 to 0.7) .29 Overall intervention effectd NA NA NA .17 Pain interferencee 1 wk 2.8 (2.7) 2.9 (2.5) −0.1 (−0.8 to 0.6) .71 3 mo 1.5 (2.1) 2.3 (2.4) −0.8 (−1.5 to −0.1) .02 6 mo 1.8 (2.6) 1.9 (2.3) −0.1 (−0.8 to 0.6) .87 12 mo 1.6 (2.4) 2.0 (2.5) −0.4 (−1.1 to 0.3) .30 Overall intervention effectd NA NA NA .16 Depressive symptomsf 1 wk 2.6 (4.1) 3.3 (4.3) −0.7 (−1.8 to 0.5) .26 3 mo 2.1 (3.9) 2.5 (4.1) −0.5 (−1.7 to 0.6) .36 Overall intervention effectd NA NA NA .89 Current pain intensityg 1 wk 2.3 (2.1) 2.2 (2.1) 0.1 (−0.5 to 0.7) .69 3 mo 1.5 (2.0) 2.1 (2.1) −0.6 (−1.2 to −0) .04 6 mo 1.8 (2.5) 1.8 (1.9) −0.1 (−0.7 to 0.5) .78 12 mo 1.4 (2.1) 1.7 (2.1) −0.3 (−0.9 to 0.3) .33 Overall intervention effectd NA NA NA .13 Seeking health care for low back pain, No./total No. (%) 3 mo 73/96 (76.0) 82/93 (88.2) 0.43 (0.19 to 0.93) .03 6 mo 44/95 (46.3) 48/91 (52.7) 0.77 (0.43 to 1.38) .38 12 mo 32/91 (35.2) 38/87 (43.7) 0.70 (0.38 to 1.28) .25 Global change at 3 moh 8.1 (1.7) 7.8 (2.0) −0.3 (−0.9 to 0.2) .11 Recurrence at 12 mo, No./total No. (%)i 26/91 (28.6) 41/87 (47.1) 0.44 (0.24 to 0.82) .01 Pain attitudes 1 wk 1.3 (1.2) 2.2 (1.3) −0.9 (−1.2 to −0.5) <.001 12 mo 1.2 (1.2) 1.6 (1.3) −0.4 (−0.7 to 0) .03 Overall intervention effectd NA NA NA .16 Nothing seriously wrong (0-10) at 1 wkj 7.6 (2.5) 6.5 (2.9) 1.2 (0.4 to 2.0) .003 Yes, perceive a need for further tests at 1 wk, No./total No. (%) 25/98 (25.5) 36/96 (37.5) 0.57 (0.31 to 1.05) .07 Abbreviations: NA, not applicable; OR, odds ratio.
a Data are presented as mean (SD) unless otherwise indicated.
b Reporting 2 or more on an 11-point pain intensity numeric rating scale during the past week and no periods of recovery at that time.
c Roland Morris Disability Questionnaire with range from 0 (no disability) to 24 (high disability).
d P value is from mixed models for repeated measures comparing between-group difference during the full 12-month trial, controlling for baseline and including time points as a categorical variable.
e Numeric rating scale with range from 0 (no interference) to 10 (highest interference possible).
f Depression severity scale of Depression, Anxiety, and Stress Scale with range from 0 (no depressive symptoms) to 42 (high depressive symptoms).
g Numeric rating scale with range from 0 (no pain) to 10 (worst pain possible).
h Global Back Recovery Scale.
i Recurrence was defined as answering yes to both of the following questions: (1) “In the last 6 months/12 months, has your lower back pain gone away completely for a period of more than 30 days, only to return later on?” and (2) “If yes, did the return of low back pain last at least 24 hours with a pain intensity of more than 2/10?”
j “How reassured do you feel that there is no serious condition causing your back pain?” Range from 0 (not reassured at all) to 10 (completely reassured).