You are studying the effect of your version of mindfulness training on psychopathy. You have been recording the psychopathy scores of all your clients for the past 25 years and the mean score was 68.4 (st dev = 18.1, higher numbers indicate more severe depression). You hypothesize that using mindfulness training should reduce the severity of psychopathy in your patients because research done in the past has shown consistently that the use of mindfulness training levels psychopathy. You run a small study with just 14 people who recently used your mindfulness training to estimate your effect size. You find that these 14 people had a mean score of 62.3 (st dev = 15.4). If this represents an accurate estimate, how many people would you have to include in your research to obtain a power of .85?