The literature review was done by means of the online version of the Educational Resource Information Center (ERIC) and Dissertation Abstracts International. Currently, ERIC contains either abstracts, full texts of studies, or both indexed from 1966 to the present. Keywords used in the search with various combinations were gifted, talented, personality, personality characteristics, personality types, psychological types, Myers-Briggs Type Indicator, and MBT I. Four hundred and twelve studies either in full-text or in abstract format were found. After an examination of each abstract, 63 studies were selected for further review. The rest of the studies were excluded from further investigation for three possible reasons: They were completely irrelevant to this research, they did not use the MBTI, or they were not original research.
After 63 studies we re obtained, including articles, reports, books, and dissertations, they were coded in identification forms for further review, which indicated that only 14 of them had enough data for inclusion. Each study had to report either the number of participants falling into each type, the eight basic personality types of the participants, or both to be included in this research synthesis. The 14 studies yielded 19 independent samples because some of them had more than one sample. Also, multiple studies by an author were carefully reviewed to avoid duplication in the synthesis. When sample characteristics matched in different studies by an author that were published in different journals and at different times, the one that had more data about findings and sample characteristics was included in the synthesis. Only two studies of one author (Mills, 1984; Mills & Parker, 1998) were included because there were 14 years between these two studies and the sample characteristics were significantly different. The 19 samples were then coded in sample characteristics forms and type distributions forms for inclusion.