Effects of Questionnaire Length on Response Quality

A response tendency resulting from the length of a group-administeredquestionnaire instrument is described. Respondents answeringitems that are included in large sets toward the later partsof a long questionnaire are more likely to give identical answersto most or all of the items, compared with those respondingto items in smaller sets or in shorter questionnaires. Whilemeans and intercorrelations among items within the same setare affected by this "straight-line" response pattern, intercorrelationsbetween items from different sets are much less affected byit. These investigations are based on comparisons between along questionnaire, administered to 1,050 high school seniorsin nine high schools across the nation in 1978, and five shorterquestionnaires administered to large national samples of highschool seniors.