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. Author manuscript; available in PMC: 2009 Dec 13.
Published in final edited form as: JAMA. 2009 May 13;301(18):1883–1891. doi: 10.1001/jama.2009.643

Table 2.

Arm means and differences between arm means for all outcomesa

Outcomes Intervention
(n=319)
Control
(n=322)
Mean arm
difference
(95% CI)
P-value of
arm effect:
covariate-
adjusted
(unadjusted)
Holm’s
Procedureb
Alpha Level
Baseline
Mean (se)
Change
Mean (se)
Baseline
Mean (se)
Change
Mean (se)
Primary Outcome

SF-Physical Function 75.9 (1.1) −2.15 (0.9) 75.6 (1.1) −4.84 (0.9) 2.69 0.03 (0.03)
    Range 10–100 (0.17, 5.21)

Secondary Outcomes

LLF- Basic Lower Extremity 78.4 (0.8) +0.34 (0.6) 78.1 (0.9) −1.89 (0.6) 2.24 (0.56, 3.91) 0.005 (0.005) 0.0050
    Range 45.6–100

LLF-Advanced Lower Extremity 52.8 (0.8) −0.37 (0.5) 52.9 (0.8) −2.30 (0.6) 1.92 (0.45, 3.39) 0.02 (0.01) 0.0063
    Range 0–100

Behavioral Targets

Duration of Strength Exercise (minutes/wk) 7.0 (2.1) +18.7 (2.4) 11.5 (2.5) +0.5 (2.7) 18.2 (11.2, 25.2) <0.0001 (<0.0001) 0.0029
    Range 0–600c

Duration of Endurance Exercise (minutes/wk) 24.6 (2.1) +36.3 (4.9) 28.7 (2.3) +23.4 (5.6) 12.9 (1.89, 27.6) 0.004 (0.003) 0.0042
    Range 0–149

Strength Exercise Frequency (sessions/wk) 0.5 (0.1) +1.4 (0.2) 0.5 (0.1) +0.2 (0.1) 1.12 (0.70, 1.54) <0.0001 (<0.0001) 0.0031
    Range 0–7

Endurance Exercise Frequency (sessions/wk) 1.6 (0.1) +1.6 (0.2) 1.8 (0.2) +0.5 (0.2) 1.05 (0.39, 1.72) 0.005 0.0045
    Range 0–15

Fruits & Vegetables (daily servings) 3.72 (0.1) +1.24 (0.14) 3.54 (0.1) +0.13 (0.11) 1.11 (0.76, 1.47) <0.0001 (<0.0001) 0.0033
    Range 0–15.80

Saturated Fat Intake (g/day) 19.6 (0.5) −3.06 (0.51) 19.32 (0.5) −1.07 (0.49) −1.99 (−0.58, −3.40) 0.002 (<0.0001) 0.0038
    Range 2 −57

Weight (kg) 85.7 (0.7) −2.06 (0.19) 84.7 (0.7) −0.92 (0.2) −1.14 <0.0001 0.0036
    Range 59.1 – 125.5 (−0.59, −1.69)

Body mass index 29.1 (0.2) −0.69 (0.07) 29.2 (0.2) −.031 (0.08) −0.38 <0.0001 0.0038
    Range 25.0 – 47.0 (−0.19, −0.57)

Health Quality of Life

SF-General Health 71.8 (0.9) +0.77 (0.72) 72.6 (0.9) −1.94 (0.80) 2.71 0.03 (0.02) 0.0071
    Range 15 −100 (0.58, 4.84)

SF-Pain 72.2 (1.2) −0.78 (1.07) 72.6 (1.2) −3.19 (1.22) 2.40 0.16 (0.13) 0.0167
    Range 10–100 (−0.79, 5.59)

SF-Vitality 61.9 (0.9) −0.47 (0.89) 61.5 (1.0) −2.42 (0.98) 1.95 0.10 (0.09) 0.0125
    Range 0 – 100 (−0.64, 4.55)

SF-Social Functioning 90.2 (1.0) −1.29 (1.05) 90.8 (0.9) −5.05 (1.22) 3.75 0.03 (0.02) 0.0083
    Range 12.5 – 100 (0.58, 6.92)

SF- Mental Health 85.6 (0.7) +0.50 (0.53) 86.3 (0.7) −2.04 (0.74) 2.54 0.01 (0.08) 0.0056
    Range 32 – 100 (0.75, 4.33)

SF- Role Physical 75.7 (1.9.) −2.43 (2.02) 78.6 (1.9) −4.68 (2.14) 2.25 0.32 (0.30) 0.0250
    Range 0 – 100 (−3.54, 8.05)

SF-Role Emotional 92.1 (1.2) −0.73 (1.32) 92.0 (1.2) −0.62 (1.38) −0.11 0.93 (0.98) 0.0500
    Range 0 – 100 (−3.86, 3.64)

Abbreviations: se, standard error; CI, confidence interval

a

Since the observed means and covariate-adjusted means were almost identical, only the observed means are shown. Both covariate-adjusted and unadjusted p-values for the test of the arm effects are given. Missing year-1 outcomes were imputed to baseline value.

b

Holm’s procedure first ranks the 17 p-values from lowest to highest. The first (lowest) p-value has to be less than 0.0029 (0.05/17) to be statistically significant and to permit continuation to the other t-tests. The Holm’s procedure continues sequentially in this fashion using alpha levels of 0.0.0031 (0.05/16), 0.0033 (0.05/15), … , and 0.05 (0.05/1) for the remaining 16 tests, respectively.

c

600 minutes of light strength training is an outlier (next highest value is 210). Because we were unable to validate the accuracy of this data point it was included in the analysis. Inclusion or exclusion of this value made no difference on the estimates of the p-value.