<prompt> Translate the following text to EnglishHata hivyo, wagonjwa pekee ambao walionyesha athari tofauti kutoka kwa uingiliaji mfupi walikuwa precontemptors katika kundi la miaka 13-17.  <response>: However, the only patients who showed a differential effect from the brief intervention were precontemplators in the 13- to 17-year-old group. 