The Meaning of Reliability and Validity

Biography and life story research has been criticized for being too subjective as a form of research science. It has been characterized as too unwieldy and without a set of established and agreed-on methodological procedures. The defenders claim that biography and life story methods are of value because they are the best way to study the whole person, which was the fundamental goal of personality psychology during the 1930s at its founding. Sarbin (1986) also defends these methods by arguing that narrative is the root metaphor for the entire field of psychology.

There are some ways in which biography and life story researchers think about issues of the trustworthiness and usefulness of their research design, data collection methods, and analytic strategies of inquiry. Many of the ways these researchers think about reliability and validity are shaped by the arguments that scholars have made about the need to define reliability and validity differently in qualitative research (Anfara, Brown, & Mangione, 2002; Golafshani, 2003). A key idea related to external validity has to do with representativeness. Within biography and life story research, representativeness can be thought of in terms of the appropriateness and completeness of the researcher's sampling design. A biography and life story researcher can engage in sampling among a group of individuals as well as sampling of topics and situations that the participant has conveyed to be important in making sense of her life (Brunswik, 1956; Dukes, 1965). In contrast, an experiment most often samples a single situation that is subject to the manipulation inherent in the experimental design. Thought sampling is another example of how external validity can be conceptualized within biography and life story research. This refers to sampling from within the set of life story data the thoughts that are representative of the general pattern of thinking of the individual about the meaning of his life. This form of thought sampling was described previously as part of the thematic content analysis process by which the researcher searches the life story data to understand and interpret the participant's characteristic sense of self and meaning within the cultural contexts of life.

Internal validity is often considered in terms of narrative truth (Schafer, 1981; Spence, 1982). This is the idea that a good interpretation of a life is linked to standards of a “good story,” which includes its being internally coherent. In addition to coherence, McAdams (2009) also describes “openness, credibility, differentiation, reconciliation, and generative integration” (p. 423) as characteristics of a good story. Narrative truth extends the meaning of “truth” beyond the correspondence of objective facts of a life story event. In other words, the truth is not just what happened within the person's life in her story construction (scholars sometimes call this historical truth). The truth and internal consistency are also reflected in how the person felt about the experience when it was happening and how the person feels about it in the present (Rouse, 1978).

Another consideration of validity within biography and life story research is related to generalizability. By design, biography and life story research produces rich contextualized data. As such, these data provide opportunities for scholars not only to test existing theories but also to develop theories informed by meaning and human experience contextualized within a life. From this perspective the goal of the researcher is to use the life story data to make theoretical generalizations, which are generalized statements for which interpretive evidence can be found in the life story data.

The issues related to reliability and validity of life story data are complicated. Biography and life story researchers who disseminate their research in peer-reviewed journals that typically do not publish this type of research often are criticized by peer reviewers because of the ways in which validity and reliability are established within biography and life story research. This marks another of the many complexities inherent in the process of producing rich and thick descriptions of lives and their meaning. Nonetheless, biography and life story researchers have been successful in broadly disseminating their research in some peer-reviewed journals.