THE EFFECTS OF OBSERVER PRESENCE ON THE ACTIVITY LEVEL OF FAMILIES 1

Abstract

In the present study, the possibility that the act of observing behavior may result in changes in those behaviors was investigated. An investigation of reactivity is important to the validity of research findings because the result obtained when observers are present may not generalize to situations when observers are absent. The effects of observer presence were assessed with five families, each consisting of a mother and two children, in a laboratory setting designed to resemble a typical family living room, containing a table, couch, chairs, toys, books, and a bathroom and kitchen area. The families were each exposed to a sequence of four 30‐minute conditions during which an observer was alternatively physically present or absent from the room. From behind an unobtrusive one‐way mirror, family members' locations were recorded every 15 seconds on gridded floor‐plan diagrams drawn to the scale of the room. After all data were collected, lines were drawn for each family member connecting the numbers sequentially and a map‐reading device was then used to measure the distance covered during each minute of observation. The presence of observers markedly reduced the activity level of all families, with the average reduction approximating 50%. However, more extended observations in natural family settings may reveal that families habituate to observer presence in a relatively short period of time. If so, the solution to the reactivity problem would involve extending the observation sessions. However, if families do not habituate, new forms of data collection might be required to guarantee the validity and generalizability of data collected by obtrusive observers.