- Email: [email protected]
Developing a scale for measuring professional equity among Canadian physicians
ARTICLE IN PRESS
Social Science & Medicine 61 (2005) 263–266 www.elsevier.com/locate/socscimed
Developing a scale for measuring professional equity among Canadian physicians Roy Thomas Dobsona,, Rein Lepnurmb, Elmer Strueningc a
College of Pharmacy and Nutrition, University of Saskatchewan, 110 Science Place, Saskatoon, Saskatchewan, Canada S7N 5C9 b College of Commerce, University of Saskatchewan, 25 Campus Drive, Saskatoon, Saskatchewan, Canada S7N 5A7 c School of Public Health, Columbia University, New York, USA Available online 19 January 2005
Abstract This paper reports on progress made in defining and measuring the concept of professional equity through the development of a summative measure of professional equity and three of its components: financial, intrinsic and recognition equity. The study sample consisted of a stratified sample of 8375 Canadian physicians with usable responses from 2749 (32.8%). Following preliminary components analysis, items were grouped into constructs. Reliability of the constructs was then determined using Cronbach’s alpha and total inter-item correlations followed by confirmatory factor analysis. A summary scale using all 15 equity items yielded a reliability: Cronbach’s alpha ¼ 0.86. The sub-scales reliabilities were: financial equity (Cronbach’s alpha ¼ 0.91); intrinsic equity (Cronbach’s alpha ¼ 0.86); and recognition equity (Cronbach’s alpha ¼ 0.70). The professional equity measures reported are therefore capable of assessing different aspects of equity and represent an advance over more general effort–reward scales or those that only measure the range of rewards. r 2004 Elsevier Ltd. All rights reserved. Keywords: Equity; Measures; Principal component analysis; Reliability; Canada
Introduction Equity theory argues individuals are motivated to maintain a balance between the value of their own contributions and the rewards they receive (Longest, 1996). For physicians, this balance includes contributions such as financial investment, expertise, and time and a wide range of rewards, both intrinsic and extrinsic. Intrinsic rewards for physicians would include such things as the interesting or personally gratifying aspects of the work itself. Extrinsic rewards can be tangible (financial compensation) or intangible (prestige and Corresponding author. Tel.: +1 306 966 6363; fax: +1 306 966 6377. E-mail address: [email protected] (R.T. Dobson).
status) (Ben-Sira, 1986). Intangible rewards can also include appreciation, respect and acknowledgement (Arnetz, 2001). If the exchange between inputs and rewards is perceived to be unfair, the affected person will become distressed (Austin, McGinn, & Susmilch, 1980; Walster, Berscheid, & Walster, 1973), and highly motivated to restore equity (Witt & Nye, 1992). Restoration of equity is sought either by changing the value attached to the exchange or by modifying the components of the exchange (Hatfield & Sprecher, 1984). The distress created by inequity has the potential to affect the health of affected physicians (Siegrist, 1996). More than 20 years ago, Karasek (1979), theorized that an excess of stress creates a physiological response, including increased risk of coronary heart disease. If left
0277-9536/$ - see front matter r 2004 Elsevier Ltd. All rights reserved. doi:10.1016/j.socscimed.2004.11.053
ARTICLE IN PRESS 264
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unattended, this can lead to depersonalization and burnout (Bosma, Richard, Johannes, & Michael, 1998; Shaufeli, Enzmann, & Girault, 1993). The distress associated with inequity can also lead to emotional distancing by physicians from their patients (Bakker, Schaufeli, Sixma, Bosveld, & Van Dierendonck, 2000; Van Dierendonck, Schafeli, & Buunk, 1996). The literature identifies a number of factors that might be considered when rewarding physicians (Feldham, Hillson, & Wingert, 1994; Hsiao, Braun, Yntema, & Becker, 1988). What is less well known is how these factors might be related to perceptions of professional equity. This paper reports on progress made in further defining and measuring the concept of professional equity (Dobson & Lepnurm, 2000) through the development of a summative measure of equity and three of its components: intrinsic, recognition and financial equity.
Methods The data used to establish the professional equity scales were taken from baseline data collected in April–May 2002 as part of a comprehensive longitudinal survey of physicians across Canada. The study population was all physicians in active practise in Canada as of January 2002. Of the 8375 eligible physicians in the sample frame, 2771 returned the survey. Of these, 22 were set aside as incomplete, resulting in 2749 (32.8%) usable responses. As the intent of developing these scales was to evaluate professional equity among physicians in clinical practice, those employed mainly in administration, community health or medical research were not included. After excluding these non-clinical physicians, the final number of responding physicians was 2619. Factor analysis with principal component analysis was used to establish the maximum amount of variance that could be explained with the fewest possible factors. While principal component analysis can establish parsimony and the relative independence of the factors, the factors must be rotated to ensure that the factors are conceptually meaningful. Statistically uncorrelated components, obtained by orthogonal rotation, are preferred because they can represent a more complex set of arrangements, even though oblique rotation can often result in more interpretable components. Orthogonal factor rotations, using the Varimax procedure of SPSS were carried out in this study to identify the independent components. Due to the possibility that missing data were not dispersed randomly, principal components analysis was carried out using only complete cases. Following preliminary components analysis, items were grouped into constructs according to factor loadings with 0.400 as the lower cut-off. The reliability of the constructs was then determined using Cronbach’s
alpha and total inter-item correlations. Alphas greater than 0.70 were considered to be acceptable for construct reliability. Finally, confirmatory factor analysis was conducted using only items contributing significantly to the scales with a total inter-item correlation of greater than 0.30.
Results The initial (Varimax) rotation with 21 items produced six distinct factors with eigenvalues greater than one, explaining more than 60% of the variance. The analysis was rerun with the same items forced into the four factors originally anticipated; however, contribution to variance and construct reliability fell off substantially after the first three factors. The final rotation was carried out using only those items associated with the first three factors. Fifteen items (Table 1) were loaded onto three factors explaining more than 62% of variance. The sub-scales reliabilities were: financial equity (Cronbach’s alpha ¼ 0.91); intrinsic equity (Cronbach’s alpha ¼ 0.86); and recognition equity (Cronbach’s alpha ¼ 0.70). The summary scale using all 15 equity items yielded a reliability of Cronbach’s alpha ¼ 0.86. The subscales were significantly correlated owing to the large sample size. However, the strength of the correlations was low to moderate (Finance and Intrinsic r ¼ 0:237; Finance and Recognition r ¼ 0:311; Intrinsic and Recognition r ¼ 0:500). Additional analysis using oblique rotation (results not shown) did not change the assigning of items to the three equity components. In addition to displaying good to excellent reliabilities, the equity scales also displayed normal distributions with limited skewing. The scores for financial equity ranged from 5 to 30 with a mean value of 17.82 (SD 6.07). Intrinsic equity scores ranged from 5 to 29 with a mean value of 13.04 (SD 3.57) suggesting that the physicians experienced greater intrinsic equity in their work compared to financial equity. Recognition equity scores ranged from 5 to 30 with a mean value of 15.75 (SD 3.87). The summative equity scale (financial plus intrinsic plus recognition) ranged from 16 to 74 with a mean value of 46.65 (SD 10.17).
Discussion Equity theory suggests that any perceived imbalance between contributions and rewards will cause perceptions of inequity and distress (Bakker et al., 2000; Van Dierendonck, Wilmar, Schaufeli, & Sixma, 1994; Mowday, 1991) and the affected person will become highly motivated to restore equity (Witt & Nye, 1992). Relying on financial incentives alone to compensate for high
ARTICLE IN PRESS R.T. Dobson et al. / Social Science & Medicine 61 (2005) 263–266
265
Table 1 Final rotated component matrix and reliability of professional equity constructs Item
Component 1
Income Income Income Income Income
reflects reflects reflects reflects reflects
responsibilities qualifications stress for risky decisions time spent practice expense
Cronbach’s alpha 2
3
0.904 0.879 0.860 0.853 0.686
Proportion of interesting work Sense of personal gratification Sense of accomplishment Sense of contributing to society Proportion of uninteresting work
0.91
0.827 0.812 0.798 0.737 0.661
Extra effort worth the recognition Administrators understand your stress Patients appreciate the care you provide Nurses show respect Degree of prestige in your community
levels of stress is likely to fail because they may be seen as a form of coercion (Herzberg & Frederick, 1987). Moreover, sustained and intensive efforts rewarded by financial means, at the expense of intrinsic rewards and recognition by peers and patients, may have adverse effects on health (Siegrist, 1996). Therefore, developing equity scales that cover a range of rewards would be useful, especially among professional groups where intrinsic and intangible factors are likely to assume greater importance for those comparing inputs and outputs. The professional equity measures reported here are capable of assessing different aspects of equity and also the degree of fairness of the exchanges. These measures represent an advance over more general ‘‘effort–reward’’ scales (VanYperen, 1996), or those that only measure the range of rewards (Ben-Sira, 1986), by linking specific demands of the medical practice with different types of rewards. The low response rate (32.8%) is a limitation of the study. Although non-response testing was carried out in association with this study, there is still the potential for non-response bias. Work is ongoing to further test and refine the scale, as well as to improve the response rate to reduce this threat to validity and to improve generalizability.
Acknowledgements This research is supported by an operating grant (FRN:50295) from the Canadian Institutes for Health Research—Regional Partnership Program.
0.86
0.749 0.686 0.599 0.599 0.523
0.70
References Arnetz, B. B. (2001). Psychosocial challenges facing physicians of today. Social Science and Medicine, 52(1), 203–213. Austin, W., McGinn, N. C., & Susmilch, C. (1980). Internal standards revisited: effects of social comparisons and expectancies on judgements of fairness and satisfaction. Journal of Experimental Social Psychology, 16, 426–441. Bakker, A. B., Schaufeli, W. B., Sixma, H. J., Bosveld, W., & Van Dierendonck, D. (2000). Patient demands, lack of reciprocity, and burnout: a five-year longitudinal study among general practitioners. Journal of Organizational Behavior, 21, 425–441. Ben-Sira, Z. (1986). The plight of primary medical care: the problematics of ‘committedness’ to the practice. Social Science and Medicine, 22(7), 699–712. Bosma, H., Richard, P., Johannes, S., & Michael, M. (1998). Two alternative job stress models and the risk of coronary heart disease. American Journal of Public Health, 88(1), 68–74. Dobson, R., & Lepnurm, R. (2000). Wellness activities address inequities. Social Science and Medicine, 50(1), 107–121. Feldham, R., Hillson, S., & Wingert, T. (1994). Measuring the dimensions of physician work. Medical Care, 32(9), 943–957. Hatfield, E., & Sprecher, S. (1984). Equity theory and behavior in organizations. Research in the Sociology of Organizations, 3, 95–124. Herzberg, & Frederick (1987). One more time: how do you motivate employees? Harvard Business Review, 16(September–October), 109–120. Hsiao, W. C., Braun, P., Yntema, D., & Becker, E. R. (1988). Estimating physicians’ work for a resource-based relative-value scale. New England Journal of Medicine, 319, 835–841.
ARTICLE IN PRESS 266
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Karasek, R. A. (1979). Job demands, job decision latitude, and mental strain: implications for job redesign. Administrative Science Quarterly, 24, 285–307. Longest, B. B. (1996). Leading through motivation. In Health professionals in management (pp. 245–276). Stamford, Connecticut: Appleton and Lange. Mowday, R. T. (1991). Equity theory perceptions of behavior in organizations. In R. M. Steers, & I. W. Porter (Eds.), Motivation & work behavior (pp. 111–131). New York: McGraw-Hill Publishers. Shaufeli, W. B., Enzmann, D., & Girault, N. (1993). The measurement of burnout: a review. In W. B. Shaufeli, C. Maslach, & T. Marek (Eds.), Professional burnout: recent developments in theory & research (pp. 199–215). New York: Hemisphere. Siegrist, J. (1996). Adverse health effects of high-effort/low reward conditions. Journal of Occupational Health Psychology, 1(1), 27–41.
Van Dierendonck, D., Schafeli, W. B., & Buunk, A. P. (1996). Inequity among human service professionals: measurement and relation to burnout. Basic and Applied Social Psychology, 18, 429–451. Van Dierendonck, D., Wilmar, B., Schaufeli, W. B., & Sixma, H. J. (1994). Burnout among general practitioners: a perspective from equity theory. Journal of Social and Clinical Psychology, 13(1), 86–100. VanYperen, N. W. (1996). Communal orientation and the burnout syndrome among nurses: a replication and extension. Journal of Applied Social Psychology, 26(4), 338–354. Walster, E., Berscheid, E., & Walster, G. W. (1973). New directions in equity research. Journal of Personality and Social Psychology, 25, 151–176. Witt, L. A., & Nye, L. G. (1992). Gender and the relationship between perceived fairness of pay or promotion and job satisfaction. Journal of Applied Psychology, 77(6), 910–917.
Social Science & Medicine 61 (2005) 263–266 www.elsevier.com/locate/socscimed
Developing a scale for measuring professional equity among Canadian physicians Roy Thomas Dobsona,, Rein Lepnurmb, Elmer Strueningc a
College of Pharmacy and Nutrition, University of Saskatchewan, 110 Science Place, Saskatoon, Saskatchewan, Canada S7N 5C9 b College of Commerce, University of Saskatchewan, 25 Campus Drive, Saskatoon, Saskatchewan, Canada S7N 5A7 c School of Public Health, Columbia University, New York, USA Available online 19 January 2005
Abstract This paper reports on progress made in defining and measuring the concept of professional equity through the development of a summative measure of professional equity and three of its components: financial, intrinsic and recognition equity. The study sample consisted of a stratified sample of 8375 Canadian physicians with usable responses from 2749 (32.8%). Following preliminary components analysis, items were grouped into constructs. Reliability of the constructs was then determined using Cronbach’s alpha and total inter-item correlations followed by confirmatory factor analysis. A summary scale using all 15 equity items yielded a reliability: Cronbach’s alpha ¼ 0.86. The sub-scales reliabilities were: financial equity (Cronbach’s alpha ¼ 0.91); intrinsic equity (Cronbach’s alpha ¼ 0.86); and recognition equity (Cronbach’s alpha ¼ 0.70). The professional equity measures reported are therefore capable of assessing different aspects of equity and represent an advance over more general effort–reward scales or those that only measure the range of rewards. r 2004 Elsevier Ltd. All rights reserved. Keywords: Equity; Measures; Principal component analysis; Reliability; Canada
Introduction Equity theory argues individuals are motivated to maintain a balance between the value of their own contributions and the rewards they receive (Longest, 1996). For physicians, this balance includes contributions such as financial investment, expertise, and time and a wide range of rewards, both intrinsic and extrinsic. Intrinsic rewards for physicians would include such things as the interesting or personally gratifying aspects of the work itself. Extrinsic rewards can be tangible (financial compensation) or intangible (prestige and Corresponding author. Tel.: +1 306 966 6363; fax: +1 306 966 6377. E-mail address: [email protected] (R.T. Dobson).
status) (Ben-Sira, 1986). Intangible rewards can also include appreciation, respect and acknowledgement (Arnetz, 2001). If the exchange between inputs and rewards is perceived to be unfair, the affected person will become distressed (Austin, McGinn, & Susmilch, 1980; Walster, Berscheid, & Walster, 1973), and highly motivated to restore equity (Witt & Nye, 1992). Restoration of equity is sought either by changing the value attached to the exchange or by modifying the components of the exchange (Hatfield & Sprecher, 1984). The distress created by inequity has the potential to affect the health of affected physicians (Siegrist, 1996). More than 20 years ago, Karasek (1979), theorized that an excess of stress creates a physiological response, including increased risk of coronary heart disease. If left
0277-9536/$ - see front matter r 2004 Elsevier Ltd. All rights reserved. doi:10.1016/j.socscimed.2004.11.053
ARTICLE IN PRESS 264
R.T. Dobson et al. / Social Science & Medicine 61 (2005) 263–266
unattended, this can lead to depersonalization and burnout (Bosma, Richard, Johannes, & Michael, 1998; Shaufeli, Enzmann, & Girault, 1993). The distress associated with inequity can also lead to emotional distancing by physicians from their patients (Bakker, Schaufeli, Sixma, Bosveld, & Van Dierendonck, 2000; Van Dierendonck, Schafeli, & Buunk, 1996). The literature identifies a number of factors that might be considered when rewarding physicians (Feldham, Hillson, & Wingert, 1994; Hsiao, Braun, Yntema, & Becker, 1988). What is less well known is how these factors might be related to perceptions of professional equity. This paper reports on progress made in further defining and measuring the concept of professional equity (Dobson & Lepnurm, 2000) through the development of a summative measure of equity and three of its components: intrinsic, recognition and financial equity.
Methods The data used to establish the professional equity scales were taken from baseline data collected in April–May 2002 as part of a comprehensive longitudinal survey of physicians across Canada. The study population was all physicians in active practise in Canada as of January 2002. Of the 8375 eligible physicians in the sample frame, 2771 returned the survey. Of these, 22 were set aside as incomplete, resulting in 2749 (32.8%) usable responses. As the intent of developing these scales was to evaluate professional equity among physicians in clinical practice, those employed mainly in administration, community health or medical research were not included. After excluding these non-clinical physicians, the final number of responding physicians was 2619. Factor analysis with principal component analysis was used to establish the maximum amount of variance that could be explained with the fewest possible factors. While principal component analysis can establish parsimony and the relative independence of the factors, the factors must be rotated to ensure that the factors are conceptually meaningful. Statistically uncorrelated components, obtained by orthogonal rotation, are preferred because they can represent a more complex set of arrangements, even though oblique rotation can often result in more interpretable components. Orthogonal factor rotations, using the Varimax procedure of SPSS were carried out in this study to identify the independent components. Due to the possibility that missing data were not dispersed randomly, principal components analysis was carried out using only complete cases. Following preliminary components analysis, items were grouped into constructs according to factor loadings with 0.400 as the lower cut-off. The reliability of the constructs was then determined using Cronbach’s
alpha and total inter-item correlations. Alphas greater than 0.70 were considered to be acceptable for construct reliability. Finally, confirmatory factor analysis was conducted using only items contributing significantly to the scales with a total inter-item correlation of greater than 0.30.
Results The initial (Varimax) rotation with 21 items produced six distinct factors with eigenvalues greater than one, explaining more than 60% of the variance. The analysis was rerun with the same items forced into the four factors originally anticipated; however, contribution to variance and construct reliability fell off substantially after the first three factors. The final rotation was carried out using only those items associated with the first three factors. Fifteen items (Table 1) were loaded onto three factors explaining more than 62% of variance. The sub-scales reliabilities were: financial equity (Cronbach’s alpha ¼ 0.91); intrinsic equity (Cronbach’s alpha ¼ 0.86); and recognition equity (Cronbach’s alpha ¼ 0.70). The summary scale using all 15 equity items yielded a reliability of Cronbach’s alpha ¼ 0.86. The subscales were significantly correlated owing to the large sample size. However, the strength of the correlations was low to moderate (Finance and Intrinsic r ¼ 0:237; Finance and Recognition r ¼ 0:311; Intrinsic and Recognition r ¼ 0:500). Additional analysis using oblique rotation (results not shown) did not change the assigning of items to the three equity components. In addition to displaying good to excellent reliabilities, the equity scales also displayed normal distributions with limited skewing. The scores for financial equity ranged from 5 to 30 with a mean value of 17.82 (SD 6.07). Intrinsic equity scores ranged from 5 to 29 with a mean value of 13.04 (SD 3.57) suggesting that the physicians experienced greater intrinsic equity in their work compared to financial equity. Recognition equity scores ranged from 5 to 30 with a mean value of 15.75 (SD 3.87). The summative equity scale (financial plus intrinsic plus recognition) ranged from 16 to 74 with a mean value of 46.65 (SD 10.17).
Discussion Equity theory suggests that any perceived imbalance between contributions and rewards will cause perceptions of inequity and distress (Bakker et al., 2000; Van Dierendonck, Wilmar, Schaufeli, & Sixma, 1994; Mowday, 1991) and the affected person will become highly motivated to restore equity (Witt & Nye, 1992). Relying on financial incentives alone to compensate for high
ARTICLE IN PRESS R.T. Dobson et al. / Social Science & Medicine 61 (2005) 263–266
265
Table 1 Final rotated component matrix and reliability of professional equity constructs Item
Component 1
Income Income Income Income Income
reflects reflects reflects reflects reflects
responsibilities qualifications stress for risky decisions time spent practice expense
Cronbach’s alpha 2
3
0.904 0.879 0.860 0.853 0.686
Proportion of interesting work Sense of personal gratification Sense of accomplishment Sense of contributing to society Proportion of uninteresting work
0.91
0.827 0.812 0.798 0.737 0.661
Extra effort worth the recognition Administrators understand your stress Patients appreciate the care you provide Nurses show respect Degree of prestige in your community
levels of stress is likely to fail because they may be seen as a form of coercion (Herzberg & Frederick, 1987). Moreover, sustained and intensive efforts rewarded by financial means, at the expense of intrinsic rewards and recognition by peers and patients, may have adverse effects on health (Siegrist, 1996). Therefore, developing equity scales that cover a range of rewards would be useful, especially among professional groups where intrinsic and intangible factors are likely to assume greater importance for those comparing inputs and outputs. The professional equity measures reported here are capable of assessing different aspects of equity and also the degree of fairness of the exchanges. These measures represent an advance over more general ‘‘effort–reward’’ scales (VanYperen, 1996), or those that only measure the range of rewards (Ben-Sira, 1986), by linking specific demands of the medical practice with different types of rewards. The low response rate (32.8%) is a limitation of the study. Although non-response testing was carried out in association with this study, there is still the potential for non-response bias. Work is ongoing to further test and refine the scale, as well as to improve the response rate to reduce this threat to validity and to improve generalizability.
Acknowledgements This research is supported by an operating grant (FRN:50295) from the Canadian Institutes for Health Research—Regional Partnership Program.
0.86
0.749 0.686 0.599 0.599 0.523
0.70
References Arnetz, B. B. (2001). Psychosocial challenges facing physicians of today. Social Science and Medicine, 52(1), 203–213. Austin, W., McGinn, N. C., & Susmilch, C. (1980). Internal standards revisited: effects of social comparisons and expectancies on judgements of fairness and satisfaction. Journal of Experimental Social Psychology, 16, 426–441. Bakker, A. B., Schaufeli, W. B., Sixma, H. J., Bosveld, W., & Van Dierendonck, D. (2000). Patient demands, lack of reciprocity, and burnout: a five-year longitudinal study among general practitioners. Journal of Organizational Behavior, 21, 425–441. Ben-Sira, Z. (1986). The plight of primary medical care: the problematics of ‘committedness’ to the practice. Social Science and Medicine, 22(7), 699–712. Bosma, H., Richard, P., Johannes, S., & Michael, M. (1998). Two alternative job stress models and the risk of coronary heart disease. American Journal of Public Health, 88(1), 68–74. Dobson, R., & Lepnurm, R. (2000). Wellness activities address inequities. Social Science and Medicine, 50(1), 107–121. Feldham, R., Hillson, S., & Wingert, T. (1994). Measuring the dimensions of physician work. Medical Care, 32(9), 943–957. Hatfield, E., & Sprecher, S. (1984). Equity theory and behavior in organizations. Research in the Sociology of Organizations, 3, 95–124. Herzberg, & Frederick (1987). One more time: how do you motivate employees? Harvard Business Review, 16(September–October), 109–120. Hsiao, W. C., Braun, P., Yntema, D., & Becker, E. R. (1988). Estimating physicians’ work for a resource-based relative-value scale. New England Journal of Medicine, 319, 835–841.
ARTICLE IN PRESS 266
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Karasek, R. A. (1979). Job demands, job decision latitude, and mental strain: implications for job redesign. Administrative Science Quarterly, 24, 285–307. Longest, B. B. (1996). Leading through motivation. In Health professionals in management (pp. 245–276). Stamford, Connecticut: Appleton and Lange. Mowday, R. T. (1991). Equity theory perceptions of behavior in organizations. In R. M. Steers, & I. W. Porter (Eds.), Motivation & work behavior (pp. 111–131). New York: McGraw-Hill Publishers. Shaufeli, W. B., Enzmann, D., & Girault, N. (1993). The measurement of burnout: a review. In W. B. Shaufeli, C. Maslach, & T. Marek (Eds.), Professional burnout: recent developments in theory & research (pp. 199–215). New York: Hemisphere. Siegrist, J. (1996). Adverse health effects of high-effort/low reward conditions. Journal of Occupational Health Psychology, 1(1), 27–41.
Van Dierendonck, D., Schafeli, W. B., & Buunk, A. P. (1996). Inequity among human service professionals: measurement and relation to burnout. Basic and Applied Social Psychology, 18, 429–451. Van Dierendonck, D., Wilmar, B., Schaufeli, W. B., & Sixma, H. J. (1994). Burnout among general practitioners: a perspective from equity theory. Journal of Social and Clinical Psychology, 13(1), 86–100. VanYperen, N. W. (1996). Communal orientation and the burnout syndrome among nurses: a replication and extension. Journal of Applied Social Psychology, 26(4), 338–354. Walster, E., Berscheid, E., & Walster, G. W. (1973). New directions in equity research. Journal of Personality and Social Psychology, 25, 151–176. Witt, L. A., & Nye, L. G. (1992). Gender and the relationship between perceived fairness of pay or promotion and job satisfaction. Journal of Applied Psychology, 77(6), 910–917.