The DOI matches its Crossref record; 25 of the 26 references it cites were found in a registry or an index.
What is coefficient alpha? An examination of theory and applications
Abstract
Psychological research involving scale construction has been hindered considerably by a wide-spread lack of understanding of coefficient alpha and reliability theory in general. A discussion of the assumptions and meaning of coefficient alpha is presented. This discussion is followed by a demonstration of the effects of test length and dimensionality on alpha by calculating the statistic for hypothetical tests with varying numbers of items, numbers of orthogonal dimensions, and average item intercorrelations. Recommendations for the proper use of coefficient alpha are of-fered. Coefficient alpha (Cronbach, 1951) is certainly one of the most important and pervasive statistics in research involving test construction and use. A review of the Social Sciences Cita-tions Index for the literature from 1966 to 1990 revealed that Cronbach's (1951) article had been cited approximately 60 times per year and in a total of 278 different journals. In addi-tion to the areas of psychology in which one may expect to see alpha used, such as educational, industrial, social, clinical, child, community, and abnormal psychology, this list of jour-nals included representatives from experimental psychology, so-ciology, statistics, medicine, counseling, nursing, economics,
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“The reliability of each scale was tested with the Cronbach's Alpha: all the values are over 0.7, which implies that there is an overall adequate internal consistency and that the measures could be considered reliable (Cortina, 1993;Taber, 2017).”
From The self-reinforcing effect of digital and social exclusion: The inequality loop (2022) · cites this paper as Cortina, 1993
In the citing paper
“Internal consistency reliability (Cronbach’s alpha) ranged from 0.70 to 0.79, which is within what is generally considered the acceptable range of 0.65–0.80 [47,48]”
From Gender Differences in Coping and Psychological Adaptation during the COVID-19 Pandemic (2023) · cites this paper as [47]
In the citing paper
“We chose these two tools, instead of traditional measures of internal consistency (i.e., Cronbach's Alpha [Cronbach, 1951] or KR-20 for dichotomous data [Kuder and Richardson, 1937]) because unlike traditional estimates which do not assess homogeneity (Cortina, 1993; Clark and Watson, 1995), omega and CFA, simultaneously provide estimates of both.”
From A psychometric analysis of the reading the mind in the eyes test: toward a brief form for research and applied settings (2015) · cites this paper as Cortina, 1993
In the citing paper
“Also, Cronbach's alpha is highly biased by long tests; Cortina (1993) recommended Cronbach's alpha not be used for tests with more than 40 items and the Eyes Test, at 36 items, is close to this limit.”
From A psychometric analysis of the reading the mind in the eyes test: toward a brief form for research and applied settings (2015) · cites this paper as Cortina, 1993
In the citing paper
“Reliability estimates are biased towards number of items, and on scales with small numbers of items the alpha is a poor indicator of measure fit (Cortina 1993).”
From Sleep Problems Across Development: A Pathway to Adolescent Risk Taking Through Working Memory (2015) · cites this paper as Cortina 1993
Citations
Cites
Coefficient Alpha and the Internal Structure of Tests
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Cited by
Sorted by citations
Items 1,001–1,051 of 1,051
Ponterotto, J. G., & Charter, R. A. (2009) · Perceptual and Motor Skills · doi:10.2466/pms.108.3.878-886 · Cited by 63
“Cortina (1993) argues that for tests of 14 or more items, a coefficient alpha of .70 can be reached even if the test consists of two orthogonal dimensions with only modest (i.e., .30) item intercorrelations.”
BackgroundOsório, F. D. L., Crippa, J. A. S., & Loureiro, S. R. (2008) · Revista Brasileira de Psiquiatria · doi:10.1590/s1516-44462008005000018 · Cited by 61
Adkins, T., Reisz, S., Hasdemir, D., & Fonagy, P. (2022) · Development and Psychopathology · doi:10.1017/s095457942000214x · Cited by 60
Insomnia in paediatric chronic pain and its impact on depression and functional disability
Kanstrup, M., Holmström, L., Ringström, R., & Wicksell, R. K. (2014) · European Journal of Pain · doi:10.1002/j.1532-2149.2013.00450.x · Cited by 59
“Chronbach’s α was used to assess the internal consistency of ISI items, where α > 0.80 is considered adequate and α > 0.90 is considered excellent (Cortina, 1993).”
MethodInfluentialCognitive insight in inpatients with psychotic, bipolar, and major depressive disorders.
Colis, M. J., Steer, R. A., & Beck, A. T. (2006) · Journal of Psychopathology and Behavioral Assessment · doi:10.1007/s10862-005-9012-7 · Cited by 58
“Because both subscales are composed of Cortina, 1993 ), even though both coefficient αs were less than the .70 value recommended by Nunnally (1978).”
BackgroundArtificial intelligence tools utilized in nursing education: incidence and associated factors
Jallad, S. T., Alsaqer, K., Albadareen, B. I., & Al-maghaireh, D. (2024) · Nurse Education Today · doi:10.1016/j.nedt.2024.106355 · Cited by 58
“Just Let Me Play!”—Understanding Constraints That Limit Adolescent Sport Participation
Casper, J. M., Bocarro, J. N., Kanters, M. A., & Floyd, M. F. (2011) · Journal of Physical Activity and Health · doi:10.1123/jpah.8.s1.s32 · Cited by 56
Pellas, N. (2025) · Education Sciences · doi:10.3390/educsci15010102 · Cited by 56
Exploring creativity in human-AI co-creation: a comparative study across design experience
Wang, N., Kim, H., Peng, J., & Wang, J. (2025) · Frontiers in Computer Science · doi:10.3389/fcomp.2025.1672735 · Cited by 59
A systematic review of sexual distress measures
Santos-Iglesias, P., Mohamed, B., & Walker, L. M. (2018) · The Journal of Sexual Medicine · doi:10.1016/j.jsxm.2018.02.020 · Cited by 51
McKenna, S. P., Doward, L. C., & Davey, K. M. (1998) · Clinical Drug Investigation · doi:10.2165/00044011-199815050-00006 · Cited by 48
Ribeiro, J. D., Yen, S., Joiner, T., & Siegler, I. C. (2015) · Journal of Affective Disorders · doi:10.1016/j.jad.2015.07.037 · Cited by 48
“…measure of capability, coefficient alpha may not provide the best index of reliability, given that alpha is designed an index of item homogeneity (Cortina, 1993; Schmitt, 1996) and the capability scale is designed to measure a heterogeneous construct comprised of two factors (pain tolerance and…”
BackgroundMettler, T., & Winter, R. (2016) · Journal of Information Technology · doi:10.1057/jit.2015.28 · Cited by 47
“According to Cortina (1993), the values for α should be greater than or equal to 0.8 for a good scale, 0.7 for an acceptable scale, and 0.6 for a scale that will be used for exploratory purposes.”
InfluentialKil, N., Kim, J., McDaniel, J. T., Kim, J., & Kensinger, K. (2021) · Health Promotion Perspectives · doi:10.34172/hpp.2021.06 · Cited by 49
“29 The alpha coefficients of traditional social communication use and application-based social network service use are 0.61 and 0.65, respectively.”
InfluentialCalati, R., Cohen, L. J., Schuck, A., Levy, D., Bloch-Elkouby, S., Barzilay, S., Rosenfield, P. J., & Galynker, I. (2020) · Journal of Affective Disorders · doi:10.1016/j.jad.2019.12.001 · Cited by 47
Emser, T. S., Mazzucchelli, T. G., Christiansen, H., & Sanders, M. R. (2016) · Research in Developmental Disabilities · doi:10.1016/j.ridd.2015.09.006 · Cited by 46
Kvestad, I., Taneja, S., Kumar, T., Bhandari, N., Strand, T. A., & Hysing, M. (2013) · Nutrition Journal · doi:10.1186/1475-2891-12-50 · Cited by 44
“Standardized alpha values, as appropriate when standard scores are summed to form scale scores [18], were calculated for the total score and for the five subscales for the 11 age intervals.”
BackgroundMethodFactor structure and internal consistency of a Swedish version of the pain catastrophizing scale
Kemani, M. K., Grimby‐Ekman, A., Lundgren, J., Sullivan, M., & Lundberg, M. (2019) · Acta Anaesthesiologica Scandinavica · doi:10.1111/aas.13246 · Cited by 43
“8 to be adequate.(41,42) Construct validity was additionally assessed by correlating the factor solution with the best model fit, with demographic (age, gender, and civil status) and background (pain onset, pain duration, and level of education) variables.”
BackgroundVigário, P. D. S., de Oliveira Chachamovitz, D. S., Cordeiro, M. F. N., dos Santos Teixeira, P. D. F., de Castro, C. L. N., de Oliveira, F. P., & Vaisman, M. (2011) · Thyroid® · doi:10.1089/thy.2010.0052 · Cited by 42
Cronbach’s Alpha and Semantic Overlap Between Items: A Proposed Correction and Tests of Significance
Alkhadim, G. S. (2022) · Frontiers in Psychology · doi:10.3389/fpsyg.2022.815490 · Cited by 41
“…and challenges (Shevlin et al., 2000, 229–237; Raykov, 2001, 69–76; Hayashi and Kamata, 2005, 579–586; Liu et al., 2010, 5–21) and controversies regarding computation or interpretation (Boyle, 1991, 291–294; Cortina, 1993, 98–104; Kopalle and Lehmann, 1997, 189–197; Henson, 2001, 177–189).”
The Nature and Role of Morality in Offending: A Moral Foundations Approach
Silver, J. R., & Silver, E. (2021) · Journal of Research in Crime and Delinquency · doi:10.1177/0022427820960201 · Cited by 41
“With fewer items, higha values are difficult to obtain even in the presence of adequate inter-item correlations (Cortina 1993:101).”
BackgroundKenna, G. A., Longabaugh, R., Gogineni, A., Woolard, R. H., Nirenberg, T. D., Becker, B., Minugh, P. A., Carty, K., Clifford, P. R., & Karolczuk, K. (2005) · Journal of Studies on Alcohol · doi:10.15288/jsa.2005.66.433 · Cited by 40
Yang, Y. (2018) · Journal of Service Theory and Practice · doi:10.1108/jstp-06-2017-0102 · Cited by 38
Best, P., Meireles, M., Schroeder, F., Montgomery, L., Maddock, A., Davidson, G., Galway, K., Trainor, D., Campbell, A., & Van Daele, T. (2022) · Journal of Technology in Behavioral Science · doi:10.1007/s41347-021-00214-6 · Cited by 36
“The internal consistency of this measurement was tested using a Cronbach’s alpha test of reliability, which deems that any scale measurement which is 0.7 or over is internally consistent (Cortina, 1993).”
MethodInfluentialSchmalbach, B., Roenneberg, C., Hausteiner-Wiehle, C., Henningsen, P., Brähler, E., Zenger, M., & Häuser, W. (2020) · Journal of Psychosomatic Research · doi:10.1016/j.jpsychores.2020.109991 · Cited by 32
How customer knowledge dissemination links to KAM
Salojärvi, H., Saarenketo, S., & Puumalainen, K. (2013) · Journal of Business & Industrial Marketing · doi:10.1108/08858621311330236 · Cited by 28
Skowronski, M., Busching, R., & Krahé, B. (2021) · Sex Roles · doi:10.1007/s11199-020-01187-1 · Cited by 27
“The internal consistency was acceptable (Cronbach’sα = .65) bearing inmind the low number of items (Cortina 1993).”
BackgroundIvanova, M. V., Akinina, Y. S., Soloukhina, O. A., Iskra, E. V., Buivolova, O. V., Chrabaszcz, A. V., Stupina, E. A., Khudyakova, M. V., Akhutina, T. V., & Dragoy, O. (2021) · PLOS ONE · doi:10.1371/journal.pone.0258946 · Cited by 25
Fear of negative evaluation, trait anxiety, and judgment bias in adults who stutter
Brundage, S. B., Winters, K. L., & Beilby, J. M. (2017) · American Journal of Speech-Language Pathology · doi:10.1044/2017_ajslp-16-0129 · Cited by 26
“The FNE has a high level of internal consistency, with Kuder-Richardson coefficient (KR-20) values between .92 and .94 (Leary, 1991); the Kuder-Richardson coefficient is a recognized measure of internal consistency for items with a dichotomous scale (Cortina, 1993).”
BackgroundMethodKanehara, A., Kotake, R., Miyamoto, Y., Kumakura, Y., Morita, K., Ishiura, T., Shimizu, K., Fujieda, Y., Ando, S., Kondo, S., et al. (2017) · BMC Psychiatry · doi:10.1186/s12888-017-1520-y · Cited by 23
A validation of the pain interference index in adults with long-standing pain
Kemani, M. K., Zetterqvist, V., Kanstrup, M., Holmström, L., & Wicksell, R. K. (2016) · Acta Anaesthesiologica Scandinavica · doi:10.1111/aas.12599 · Cited by 23
“85, and no item contributed negatively to the scale’s total alpha.(15)”
BackgroundMethodChallenging assignments and activating mood: the influence of goal orientation
Preenen, P. T. Y., Van Vianen, A. E. M., & De Pater, I. E. (2014) · Journal of Applied Social Psychology · doi:10.1111/jasp.12256 · Cited by 20
“52), which may be due to the low number of items (Cortina, 1993).”
BackgroundWynia, K., Middel, B., de Ruiter, H., van Dijk, J. P., Lok, W. S., de Keyser, J. H. A., & Reijneveld, S. A. (2009) · Disability and Rehabilitation · doi:10.1080/09638280802509488 · Cited by 20
“For confirmation of the factor solutions, we examined internal consistency with Cronbach’s a for each domain [15,16] and mean inter-item correlation coefficient (MICC) among the items [17].”
Methoddos Santos, L. F., Loureiro, S. R., Crippa, J. A. S., & de Lima Osório, F. (2013) · International Journal of Psychiatry in Clinical Practice · doi:10.3109/13651501.2012.710336 · Cited by 20
Norberg, M. M., Kwok, C., Crone, C., David, J., Kakar, V., & Grisham, J. R. (2020) · Journal of Obsessive-Compulsive and Related Disorders · doi:10.1016/j.jocrd.2020.100571 · Cited by 18
Kate, M.-A., Jamieson, G., Dorahy, M. J., & Middleton, W. (2021) · Journal of Trauma & Dissociation · doi:10.1080/15299732.2020.1792024 · Cited by 19
“The minimum criteria set for acceptability was r = 0.70 (Cortina, 1993).”
BackgroundInfluentialPellas, N. (2024) · Research and Practice in Technology Enhanced Learning · doi:10.58459/rptel.2025.20036 · Cited by 16
Weber, J., Heming, M., Apolinário-Hagen, J., Liszio, S., & Angerer, P. (2024) · Biological Psychology · doi:10.1016/j.biopsycho.2024.108762 · Cited by 16
“It needs to be mentioned that a small number of items and low inter-correlations naturally reduce Cronbach ’ s alpha levels (Cortina, 1993), but that intensive sampling schemes during EMA call for short measurement scales to reduce participant ’ s burden.”
BackgroundMelanou, C., & Beege, M. (2026) · Education Sciences · doi:10.3390/educsci16040651 · Cited by 12
Marini, M., Ansani, A., Demichelis, A., Mancini, G., Paglieri, F., & Viola, M. (2024) · Cognition and Emotion · doi:10.1080/02699931.2023.2296581 · Cited by 11
“The internal reliability was completely satisfactory according to the common thresholds used in the literature (Cortina, 1993; Dunn et al., 2014): Study 1: α = .82; ω = .83; Study 2: α = .83; ω = .83.”
MethodKenerson, D., Fadeyi, S., Liu, J., WERIWOH, M., Beard, K., & Hargreaves, M. K. (2017) · Journal of Health Communication · doi:10.1080/10810730.2017.1382613 · Cited by 8
“However, a low value of alpha for altruism may be due to the low number of questions for that scale (Cortina, 1993).”
BackgroundValidity Evidence of the Spanish Version of the Automatic Thoughts Questionnaire-8 in Colombia
Ruiz, F. J., Suárez-Falcón, J. C., & Riaño-Hernández, D. (2017) · The Spanish Journal of Psychology · doi:10.1017/sjp.2017.7 · Cited by 7
“In other words, measurement efficiency is an issue in this type of research because nonresponse and respondent fatigue need to be considered (Cortina, 1993; Netemeyer et al., 2002).”
BackgroundConley, S. L., Lee, S. R., Martyn, H. F., & Wu, K. D. (2019) · Journal of Obsessive-Compulsive and Related Disorders · doi:10.1016/j.jocrd.2019.100453 · Cited by 7
Goula, A., Margetis, E., Stamouli, M.-A., Latsou, D., & Gkioka, V. (2021) · Journal of Public Health Research · doi:10.4081/jphr.2021.2052 · Cited by 6
Elemo, A. S., & Türküm, A. S. (2022) · International Journal of Mental Health and Addiction · doi:10.1007/s11469-020-00475-x · Cited by 6
“It should also be noted that the internal consistency computed for the subscales and the total score for the LSAS exceed 0.60 (Cortina 1993) and range between 0.87 and 0.92, indicating sufficient reliability for using the measure in clinical settings (Rosenthal and Rosnow 1991).”
MethodInfluentialDax, V., Ftanou, M., Tran, B., Lewin, J., & Wiley, J. F. (2024) · Psycho-Oncology · doi:10.1002/pon.6262 · Cited by 3
Akgun, M., & Toker, S. (2026) · Proceedings of the 2026 CHI Conference on Human Factors in Computing Systems · doi:10.1145/3772318.3790980 · Cited by 2
“These results indicate stable internal consistency, with somewhat lower reliability for the Credibility subscale, which is expected given its smaller number of items [14, 42].”
Wu, J.-Y., Wang, K.-W. K., Liu, C.-Y., Lee, T.-T., & Huang, S.-H. (2027) · Nurse Education Today · doi:10.1016/j.nedt.2026.107364
(2011) · Amsterdam UMC (VU Amsterdam) - Institutional Repository · Cited by 1,209
Metadata
- Authors
- Cortina, J. M.
- Venue
- Journal of Applied Psychology
- Published
- 1993-02
- Volume
- 78
- Issue
- 1
- Pages
- 98-104
- ISSN
- 0021-9010 (ISSN-L)
- 1939-1854
- OpenAlex
- W2117012826
- Cited by
- 8,810
- References
- 26
- Citations by year
- 2026: 523 · 2025: 499 · 2024: 518 · 2023: 606 · 2022: 639 · 2021: 685 · 2020: 589 · 2019: 474 · 2018: 407 · 2017: 411 · 2016: 418 · 2015: 428 · 2014: 437 · 2013: 372 · 2012: 309
- FWCI
- 29.15
- Type
- journal article
- Language
- en
- Open access
- closed
- Locations
- Journal of Applied Psychology (publishedVersion)
- Topics
- Social Sciences › Decision Sciences › Management Science and Operations Research › Psychometric Methodologies and Testing
- Social Sciences › Decision Sciences › Statistics, Probability and Uncertainty › Reliability and Agreement in Measurement
- Social Sciences › Psychology › Applied Psychology › Psychological Testing and Assessment
- Keywords
- Cronbach's alpha, internal consistency, reliability theory, scale development, test length, dimensionality
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