Measuring Personality Constructs: The Advantages and Disadvantages of Self-Reports, Informant Reports and Behavioural Assessments Jennifer Dodorico McDonald University of Cambridge firstname.lastname@example.org
Achieving construct validity, or using measures that accurately represent particular theoretical constructs, is an important goal of social science research. This article reviews arguments regarding the strengths and limitations of personality assessment methods in terms of methodological feasibility and whether they are accurate in measuring personality constructs. Specifically, it considers the advantages and disadvantages of assessing personality with self-report questionnaires, informant reports, and behavioural measures. Acknowledging that no method is perfect, the discussion then focuses on the value of incorporating multiple methods. In light of the reliance on the self-report method in personality psychology, it will be argued that researchers could maximize the validity of the measurement of personality constructs by combining the questionnaire approach with other methods.
According to Cronbach and Meehl (1955), psychological and personality constructs are “postulated” or inferred characteristics or traits of a person. There are many constructs, or concepts, in psychology that are not tangible; if we cannot physically see personality traits, for instance, there is the potential to question whether they are really there. Is it possible to measure such an abstraction as ‘Conscientiousness’ in the way that physical attributes, like height, are assessed? Social scientists have been making inferences about what people are like and thus measuring these sorts of hypothetical constructs for years, which is necessary in order to more fully understand how people behave (Smith, 2005). Smith points out, though, that it is important to ensure that these theoretical constructs are measured “in a convincing, valid way” (p. 396). In general, validity of a measurement device refers to the extent to which it actually measures what it intends to measure. Construct validity, then, refers to the accuracy of a measurement of the theoretical concept (e.g. John & Soto, 2007; Messick, 1995; Ozer, 1999). Therefore, abstract personality constructs can only be accepted and made more concrete if the validity of the methods used to measure them can be ascertained. This paper will focus on evaluating the usefulness and accuracy of different methods of measuring personality constructs. According to Pervin (1999), the determining of the best methods of measuring personality constructs is one of the most prominent issues in personality psychology. The central debate involves the accuracy of self-report data in obtaining
ENQUIRE, Volume 1, Issue 1, June 2008 information about an individual’s personality, in comparison with ratings from others or the use of alternative methods of assessment. This is especially important in light of recent questionnaire findings that suggest that personality psychologists primarily rely on self-report measures, yet belong to a methodologically diverse field overall (Robins, Tracy, & Sherman, 2007). Here, I will discuss the value of considering self-reports, informant or observer reports, and behavioural measures, by presenting the advantages and disadvantages of each of these methods. I will assert that it is not sufficient to simply assume the accuracy of any one measure in fully representing the desired personality trait. I will demonstrate this by briefly addressing issues related to construct validity. Overall, this paper will suggest that a variety of methods should be employed in assessing personality constructs.
Self-Reports Advantages and disadvantages of self-reports
In order to later propose that more than one method is required to obtain more accurate understandings of personality constructs, I will discuss the value of the...