The Self subscale of the PCQ consisted of five items intended to measure how internal sources were perceived to coerce individuals into engaging in substance-abuse treatment. Both the IA and VA groups reported higher scores of perceived coercion from internal sources than from external sources, and scores were significantly higher in the VA group than in the IA group. Severe internal pressure (hitting rock bottom) often spurs people into treatment. All the questions on this subscale were related to this concept; consequently, it was not surprising that the internal domains distinguished individuals that sought voluntary treatment from those admitted involuntarily. The authors of the scale noted that “Given the complexity and multitude of pressures that [individuals with SUD] experience, it is reasonable to assume that further sub-categorization of the Self subscale might result in a more reliable and valid measure of the internal pressures that contribute to seeking treatment ”. Compared to the Australian patients in residential treatment within a therapeutic community , we found that both the IA and VA groups in our study perceived lower levels of coercion from internal sources (Australian vs. IA/VA: Self subscale 21.7 vs. 16.7/18.9).