Usually, researchers administer scales in which multiple items assess the same construct, facet, or dimension. For example, measures of job satisfaction can comprise more than 20 items. Nevertheless, some researchers have advocated that measures that comprise one item can be almost as effective, at least in some contexts. Single item measures have been used effectively to assess:
Usually, single item scales are used to represent global constructs, like job satisfaction (Wanous, Reichers, & Hudy, 1997). Nevertheless, some single item measures have been used to gauge constructs that, originally, was assumed to comprise several facets or dimensions. Certainly, because single item measures cannot differentiate these dimensions, their utility in these contexts is limited (see Youngblut & Casper, 1993).
Similarly, sometimes researchers need to differentiate various facets of some characteristic to guide future courses of action. For example, when assessing job satisfaction practitioners might want to differentiate the various facets of work to identify which initiatives to implement (Ironson, Brannick, Smith, Gibson, & Paul, 1989).
Single item measures, however, are useful when the construct is unambiguous (Wanous, Reichers, & Hudy, 1997) or when a holistic impression is informative (Youngblut & Casper, 1993). Single item measures, because of their convenience, are useful when participants are busy or ill (Waltz, Strickland, & Lenz, 1991) or perhaps dismissive of the academic pedantry that multiple item measures manifest (Wanous, Reichers, & Hudy, 1997).
The scales also vary across these dimensions. Some of these items include a visual analog scale--a straight line with anchors at each end, such as "no pain" and "worst pain ever felt (Hargreaves & Lander, 1989 & see also Luria, 1975). Second, some of the items are Likert scales, bipolar scales, or numerical rating scales. Finally, some of the single item measures use graphical representations, such as face scales (Kunin, 1955), usually to represent different levels of satisfaction (e.g., Adler & Golan, 1981), often used with children (Bieri, Reeve, Champion, Addicoat, & Ziegler, 1990).
Research indicates that single item scales can be reliable, as gauged by test-retest correlations. Test-retest reliability, for example, was elevated for single item measures of
symptom severity, psychosocial functioning, and quality of life (Zimmerman, Ruggero, Chelminski, Young, Posternak, Friedman, et al. 2006). Similarly, test retest reliability has been shown to be acceptable for single item measures of quality of life and anxiety (Youngblut & Casper, 1993).
Several studies have shown that single item scales are correlated with longer measures of psychological wellbeing. For example, in one study, single item measures of symptom severity, psychosocial functioning, and quality of life were correlaed with multuple item measures that putatively gauge the same constructs (Zimmerman, Ruggero, Chelminski, Young, Posternak, Friedman, et al. 2006).
Similar findings have emerged for measures of physical wellbeing. Correlations between single and multiple items measures of health status exceeded .5 in one study, for example (DeSalvo, Fisher, Tran, Bloser, Merrill, & Peabody, 2006).
Likewise, single item measures of global job satisfaction correlate with multiple item measures. Correlations often exceed .6 and do not vary appreciably across different scales, such as face and visual analog (Wanous, Reichers, & Hudy, 1997).
Single and multiple item measures of personality, as defined by the five factor model, also correlate highly with one another. Woods and Hampson (2005) constructed single item measures of these five traits, using bipolar scales. Correlations with multiple item scales approximated about .61.
Readiness to change, as defined by the transtheoretical model of behavioral change, has also been assessed with single item measures (Cook & Perri, 2004). These measures generate correlations of over .9 with multiple item versions (Cook & Perri, 2004).
Several studies have shown that single item scales can predict outcomes effectively. To illustrate, in one study, single item measures of symptom severity, psychosocial functioning, and quality of life differentiated individuals who were currently depressed versus individuals currently in remission (Zimmerman, Ruggero, Chelminski, Young, Posternak, Friedman, et al. 2006).
Single and multiple item measures of personality, as defined by the five factor model, also generate similar levels of criterion validity, as shown by Woods and Hampson (2005).
Indeed, Bergkvist and Rossiter (2007) showed the predictive validity of single and multiple item measures of attitudes towards advertisements and brands were approximately equal. More importantly, Nagy (2002) showed that single measures of various facets of job satisfaction explained variance in intention to leave and job performance even after the multiple item versions were controlled.
Grubb (2006), however, showed that single item measures of justice were not as effective as their multiple item counterparts. That is, correlations between justice--both procedural and interactional--and commitment to the organization were lower when single, rather than multiple, item measures were used.
Gardner, Cummings, Dunham, and Pierce (1998) examined whether single item or multiple item measures are more likely to inflate common method variance--the extent to which scales correlate merely because of overlapping variance. No apparent differences emerged (Gardner, Cummings, Dunham, & Pierce, 1998)
Some studies indicate that single item measures should not be used to represent bases of power--that is, to ascertain whether or not individuals apply coercion, offer rewards, or rely on some other means to assert their power (Schriesheim, Hinkin, & Podsakoff, 1991). Other authors, such as Loo and Kells (1998), despite showing that single item measures of job satisfaction generate excellent psychometric properties, present some caveats with this approach.
Adler, S., & Golan, J. (1981). Lateness as a withdrawal behavior. Journal of Applied Psychology, 66, 544-554.
Bergkvist, L., & Rossiter, J. R. (2007). The predictive validity of multiple-item versus single-item measures of the same constructs. Journal of Marketing Research, 44, 175-184.
Bieri, D., Reeve, R. A., Champion, G. D., Addicoat, L., & Ziegler, J. B. (1990). The Faces Pain Scale for the self-assessment of the severity of pain experienced by children: Development, initial validation, and preliminary investigation for ratio scale properties. Pain, 41, 139-150.
Cook, C. L., & Perri, M. (2004). Single-item vs multiple-item measures of stage of change in compliance with prescribed medications. Psychological Reports, 94, 115-124.
DeSalvo, K. B., Fisher, W. P., Tran, K., Bloser, N., Merrill, W., & Peabody, J. (2006). Assessing measurement properties of two single-item general health measures. Quality of Life Research: An International Journal of Quality of Life Aspects of Treatment, Care & Rehabilitation, 15, 191-201.
Gardner, D. G., Cummings, L. L& Dunham, R. B., & Pierce, J. L. (1998). Single-item versus multiple-item measurement scales: An empirical comparison. Educational and Psychological Measurement, 58, 898-915.
Gebauer, J. E., Broemer, P., Haddock, G., & von Hecker, U. (2008). Inclusion-exclusion of positive and negative past selves: Mood congruence as information. Journal of Personality and Social Psychology, 95, 470-487.
Grubb, W. L. (2006). Procedural justice and layoff survivors' commitment: A quantitative review. Psychological Reports, 99, 515-530.
Hargreaves, A., & Lander, J. (1989). Use of transcutaneous electrical nerve stimulation for postoperative pain. Nursing Research, 38, 159-161.
Hettler, T. R., & Cohen, L. H. (1998). Intrinsic religiousness as a stress-moderator for adult Protestant churchgoers. Journal of Community Psychology, 26, 597-609.
Ironson, G. H., Brannick, M. T., Smith, P. C., Gibson, W. M., & Paul, K. B. (1989). Construction of a job in general scale: A comparison of global, composite, and specific measures. Journal of Applied Psychology, 74, 193-200.
Kunin, T. (1955). The construction of a new type of attitude measure. Personnel Psychology, 8, 65-78.
Loo, R., & Kells, P. (1998). A caveat on using single-item measures. Employee Assistance Quarterly, 14, 75-80.
Nagy, M. (2002). Using a single-item approach to measure facet job satisfaction. Journal of Occupational and Organizational Psychology, 75, 77-86.
Paulhus, D. L., & Bruce, M. N. (1992). The effect of acquaintanceship on the validity of personality impressions: A longitudinal study. Journal of Personality and Social Psychology, 63, 816-824.
Robins, R. W., Hendin, H. M., & Trzesniewski, K. H. (2001). Measuring global self-esteem: Construct validation of a single-item measure and the Rosenberg Self-Esteem Scale. Personality and Social Psychology Bulletin, 27, 151-161.
Ross, M., & Wilson, A. E. (2002). It feels like yesterday: Self-esteem, valence of personal past experiences, and judgments of subjective distance. Journal of Personality and Social Psychology, 82, 792-803.
Schimmack, U., & Oishi, S. (2005). The influence of chronically and temporarily accessible information on life satisfaction judgments. Journal of Personality and Social Psychology, 89, 395-406.
Schriesheim, C. A., Hinkin, T. R., & Podsakoff, P. M. (1991). Can ipsative and single-item measures produce erroneous results in field studies of French and Raven's (1959) five bases of power? An empirical investigation. Journal of Applied Psychology, 76, 106-114.
Waltz, C. F., Strickland, O. L., & Lenz, E. R. (1991). Measurement in nursing research (2nd ed.). Philadelphia: F. A. Davis.
Wanous, J. P., & Reichers, A. E. (1996). Estimating the reliability of a single-item measure. Psychological Reports, 78, 631-634.
Wanous, J. P., Reichers, A. E., & Hudy, M. J. (1997). Overall job satisfaction: How good are single-item measures? Journal of Applied Psychology, 82, 247-252.
Williams, E. C., Horton, N. J., Samet, J. H., & Saitz, R. (2007). Do brief measures of readiness to change predict alcohol consumption and consequences in primary care patients with unhealthy alcohol use? Alcoholism: Clinical and Experimental Research, 31, 428-435.
Woods, S. A., & Hampson, S. E. (2005). Measuring the Big Five with single items using a bipolar response scale. European Journal of Personality, 19, 373-390.
Youngblut, J. M., & Casper, G. R. (1993). Single-item indicators in nursing research. Research in Nursing and Health, 16, 459-465.
Zimmerman, L., Pozehi, B., Duncan, K., & Schmitz, R. (1989). Effects of music in patients who had chronic cancer pain. Western Journal of Nursing Research, 11, 293-309.
Zimmerman, M., Ruggero, C. J., Chelminski, I., Young, D., Posternak, M. A., Friedman, M. et al. (2006). Developing brief scales for use in clinical practice: The reliability and validity of single-item self-report measures of depression symptom severity, psychosocial impairment due to depression, and quality of life. Journal of Clinical Psychiatry, 67, 1536-1541.
Last Update: 5/27/2016