<prompt> Translate the following text to EnglishMatatizo matatu yanayopatikana mara nyingi yanahusiana na kulinganisha swali ambalo mtihani aliamua kujibu na njia ya kuchagua kesi zilizochunguzwa, kuripoti msingi wa kuchagua kesi, na kuunganisha matokeo katika kesi kadhaa wakati matokeo katika moja hayakuwa sawa na yale katika nyingine.  <response>: Three problems often encountered have to do with matching the question the evaluator set out to answer and the method for selecting the instances examined, reporting the basis for selecting the instances, and integrating findings across several instances when the findings in one were inconsistent with those in another. 