Table 1

Time course of pain intensity
Estimate of the βb 95% CI p-value
(β1) Intercept 7.5 5.2 9.8 < 0.001
(β2) Coffeeic −3.5 −7.2 0.2 0.064
(β3) Timeijd 7.3 5.9 8.7 < 0.001
(β4) BP90ij −16.6 −21.1 −12.1 < 0.001
(β5) Coffeei * Timeij −2.9 −5.1 −0.7 0.011
(β6) Coffeei * BP90ij 3.4 −3.8 10.6 0.34

Estimated regression coefficients with 95% confidence intervals (CI) based on the fitted linear modelsa of the pain intensity ratings (VAS, mm) in the active side of the shoulder and neck during and after performing the 90 min computer work in subjects that had consumed (n = 19) or abstained (n = 29) from coffee before start.

aLinear mixed models for repeated measurements fitted with unstructured covariance structure.

bβ2: the difference between coffee consumers and abstainers at baseline; β3: the change per 15 min time period during the 90 min work task; β4: BP90 = break point 90 min, i.e. the change from the work task ending and through each 15 min period during the 30 min recovery; β5: the difference between coffee consumers and abstainers for each 15 min period during the work task; β6: the difference between coffee consumers and abstainers per 15 min periods during the recovery. c0 = No; 1 = Yes. d0 = Baseline; 1 = 15 min; 2 = 30 min, and so on.

Strøm et al.

Strøm et al. BMC Research Notes 2012 5:480   doi:10.1186/1756-0500-5-480

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