BEWEIS ES.

The studies below examine general methods that also appear in this journal. They do not show that this particular book works, and they are no substitute for professional advice or treatment.

• Recording progress

  A meta-analysis of 138 studies found that interventions prompting people to monitor their progress helped them reach their goals on average. The effect was larger when progress was physically recorded or reported to others.

  Source: Harkin, B., Webb, T. L., Chang, B. P. I., et al. (2016). Does monitoring goal progress promote goal attainment? A meta-analysis of the experimental evidence. Psychological Bulletin, 142(2), 198–229. (external link)

• Habits take repetition

  In one study, adults repeated a new behaviour daily in the same situation. Among participants with usable data, it took a median of 66 days for the behaviour to feel largely automatic, with wide differences between people. Missing the occasional day made little difference.

  Source: Lally, P., van Jaarsveld, C. H. M., Potts, H. W. W., & Wardle, J. (2010). How are habits formed: Modelling habit formation in the real world. European Journal of Social Psychology, 40(6), 998–1009. (external link)

• Planning concretely: when, where, how

  Plans of the form “If situation X arises, then I will do Y” showed a medium to large effect on goal attainment in a meta-analysis of 94 tests. A plan does not replace motivation; it makes the step from intention to action easier.

  Source: Gollwitzer, P. M., & Sheeran, P. (2006). Implementation intentions and goal achievement: A meta-analysis of effects and processes. Advances in Experimental Social Psychology, 38, 69–119. (external link)

• What writing can and cannot do

  Studies on writing about personal experiences show small average effects that vary widely between people and situations. A review of journaling for mental illness found a small to moderate benefit, with very mixed evidence. A journal can be a useful tool, but it is not therapy.

  Source: Frattaroli, J. (2006). Experimental disclosure and its moderators: A meta-analysis. Psychological Bulletin, 132(6), 823–865. (external link)

  Source: Sohal, M., Singh, P., Dhillon, B. S., & Gill, H. S. (2022). Efficacy of journaling in the management of mental illness: A systematic review and meta-analysis. Family Medicine and Community Health, 10(1), e001154. (external link)