Position Effects on Interview Responses1

This study investigates the effects upon response distributions of two types of position effect, the serial order in which response options for an item are presented and the location of an item in an interview. Primacy effect was statistically significant and meaningfully large in regard to evaluative items in an interview with people aged 65+; either the positive or negative end of the scale drew more responses when it was presented first. This effect was not observed for factual items. Neither was there any difference in responses to an evaluative item presented early and late in the interview, but with response options in the same order at both presentations. The results suggest that it may not be necessary to present general questions prior to specific ones in order to avoid response con-tamination, though further evidence is necessary on this point. The findings are more clear-cut in regard to the order of presentation of response options for a given item. To obtain valid group values, counterbalanced presentation is necessary; and standard scores for individuals should be used in making subgroup comparisons and other statistical procedures such as correlational analysis. ' "PHIS is an investigation of two types of posi-*- tion effect upon the response tendencies of older adults. The purpose is to determine whether the order in which stimulus material is presented in a structured interview affects responses. The two types of position effect are: (1) serial order of response options for an item and (2) position of items in the interview schedule. BACKGROUND Serial position effects have long been recog-nized in psychophysics, learning, personality, and educational and social psychology. In the design of research in these areas, careful atten-tion is paid to the order of presentation of stim-ulus material. Counterbalancing is a common design to compensate for the "effect of the rank-order in which the various treatments are administered to the same subjects " (Lindquist, 1953). The pertinent literature in the various fields is far too extensive to review here; a few references are cited as exemplary. In rote learning and retention, serial position has a dominant effect and primacy gives the most potent advantage (e.g., Ebbinghaus, 1913