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7 ACTIVE APPROACH DOES NOT ADD TO THE EFFECTS OF IN VIVO EXPOSURE 177 812.53, p < .001, η p ² = .92. Spider primes were rated as more arousing ( M = 5.73, SD = 0.97) than neutral primes ( M = 1.66, SD = 0.98), F (1,73) = 647.56, p < .001, η p ² = .90. None of this differed between conditions, all F s < 1. There was an APT effect at pretest, indicated by a more negative evaluation score for spider primes ( M = -13.48, SD = 64.19) than for neutral primes ( M = 20.29, SD = 63.19), F (1,72) = 12.39, p = .001, η p ² = .15, power = .94, which did not differ between conditions, F (2,72) = 1.44, p = .24 . This effect did not change from pre- to posttest, F < 1, nor was the crucial Time x Evaluation score x Condition interaction significant, F (2,72) = 1.25, p = .29. The difference between spider and neutral prime evaluation scores did not change for any of the conditions, which was not in line with the hypothesis that the Exposure conditions would outperform the Control condition, and Exposure + approach would show the largest effect. Pleasantness There were no differences between the conditions in how (un)pleasant the experimental procedure was rated, F < 1 ( M = 57.33, SD = 19.73). A more positive evaluation was related to a greater improvement on the BAT, r = .28, p = .02, and a lower score on the FSQ at posttest, r = -.25, p = .04. Exposure trials: time course of effects and perceived control Figure 3 depicts the time course of the steps performed during the exposure trials, and corresponding fear for Exposure + approach and Exposure only. Trend analysis indicates a linear trend for the steps performed, F (1,49) = 52.86, p < .001, η p ² = .52, power = 1.00. For fear, the trend had a quadratic shape, F (1,49) = 7.92, p = .007, η p ² = .14, power = 1.00, with a cubic aspect to it, F (1,49) = 21.81, p < .001, η p ² = .31, meaning that the line has two inflection points (it changes direction twice). Trends are similar for the two conditions, as neither interactions were significant, both F s < 1. Perceived control did not change over time, F (3.43,168.16) = 1.32, p = .27, and there was no interaction with Condition, F (3.43,168.16) = 2.06, p = .10. However, there was a trend for Condition, F (1,49) = 3.31, p = .08, η p ² = .06, power = .43. Participants in