Many people can make significant lifestyle changes and initiate recovery from SUDs without formal assistance". Within research on prevention of pregnancy and sexually transmitted diseases, a systematic review from 2003 comes to the conclusion that "no strong conclusions" can be drawn about the effectiveness of interventions based on the transtheoretical model. Again this conclusion is reached due to the inconsistency of use and implementation of the model. This study also confirms that the better stage-matched the intervention the more effect it has to encourage condom use. Within the health research domain, a 2005 systematic review of 37 randomized controlled trials claims that "there was limited evidence for the effectiveness of stage-based interventions as a basis for behavior change. Studies with which focused on increasing physical activity levels through active commute however showed that stage-matched interventions tended to have slightly more effect than non-stage matched interventions. Since many studies do not use all constructs of the TTM, additional research suggested that the effectiveness of interventions increases the better it is tailored on all core constructs of the TTM in addition to stage of change. In diabetes research the "existing data are insufficient for drawing conclusions on the benefits of the transtheoretical model" as related to dietary interventions. Again, studies with slightly different design, e.g. using different processes, proved to be effective in predicting the stage transition of intention to exercise in relation to treating patients with diabetes. TTM has generally found a greater popularity regarding research on physical activity, due to the increasing problems associated with unhealthy diets and sedentary living, e.g. obesity, cardiovascular problems. A 2011 Cochrane Systematic Review found that there is little evidence to suggest that using the transtheoretical model stages of change (TTM SOC) method is effective in helping obese and overweight people lose weight. There were only five studies in the review, two of which were later dropped due to not being relevant since they did not measure weight. Earlier in a 2009 paper, the TTM was considered to be useful in promoting physical activity. In this study, the algorithms and questionnaires that researchers used to assign people to stages of change lacked standardisation to be compared empirically, or validated. Similar criticism regarding the standardisation as well as consistency in the use of TTM is also raised in a recent review on travel interventions. With regard to travel interventions only stages of change and sometimes decisional