GEORGE A. MORGAN; ROBERT J. HARMON
In this column we provide a context for many of the types of data collection techniques used with human participants. We
will not discuss methods for assessing diagnostic status, but we will provide some information about developing or evaluating a questionnaire, test, or other data collection technique.
Research approaches or designs are approximately orthogonal
to the techniques of data collection, and thus, in theory, any type of data collection technique could be used with any approach to research. However, some types of data collection are
more commonly used with the experimental approaches. Others
are more common with comparative or associational (survey)
approaches, and still others are more common in qualitative research. Table 1 gives an approximation of how common each of several data collection techniques are within each of these three
major groupings of research approaches. Note that we have ordered the data collection techniques along a dimension from observer/ researcher report to self-report measures. The observer
report end includes observations and physiological recordings that are probably less influenced by the participants’ desire to look good, but they are affected by any biases the observer may have. Of course, if the participants realize that they are being observed, they may not behave naturally.
At the other end of this dimension are measures based on
self-reports of the participants, such as interviews and questionnaires. In these cases, responses are certainly filtered through
the participants’ eyes and are probably heavily influenced by factors such as social desirability.
Concern about faulty memories or socially desirable responses lead researchers, especially those who use experiments,
to be suspicious about the validity of the self-reports. On the other hand, observer reports are not necessarily valid measures. For example, qualitative researchers point out that cultural biases may lead observers to misinterpret their observations. In
general, it is advisable to select instruments that have been used in other studies if they have been shown to be reliable and valid with the planned types of participants and for purposes similar to that for the planned study.
TYPES OF DATA COLLECTION
Many researchers prefer systematic, direct observation of behavior as the most accurate and desirable method of recording
the behavior of children. Using direct observation, the investigator observes and records the behaviors of the participants
rather than relying on reports from parents or teachers. Observational techniques vary on several dimensions.
Naturalness of the Setting. The setting for the observations can vary from natural environments (such as a school or home) through more controlled settings (such as a laboratory playroom) to highly artificial settings (such as a physiological
laboratory). Qualitative researchers do observations almost exclusively in natural settings. Quantitative researchers use the
whole range of settings, but some prefer laboratory settings. Degree of Observer Participation. This dimension varies
from situations in which the observer is a participant to situations in which the observer is entirely unobtrusive. Most
observations, however, are done in situations in which the participants know that that observer is observing them and have
agreed to it. Such observers attempt to be unobtrusive, perhaps by observing from behind a one-way mirror.
Amount of Detail. This dimension goes from global summary
information (such as overall ratings based on the whole session) to moment-by-moment records of the observed behaviors. ObArticle 12. Data Collection Techniques
viously, the latter provides more detail, but it requires considerable preparation and training of observers.
Standardized Versus Investigator-Developed
Standardized instruments cover...