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					                                                                           Positive Affect Negative Affect Schedule:
                                                                              A Reliability Generalization Study
                                                                                                       Evie M. Muilenburg-Trevino
                                                                                                     University of Oklahoma-Tulsa,
                                                                                         Center of Applied Research for Non-profit Organizations


                                     Abstract                                             Figure 1: Boxplot of Positive Affect (PA) Reliability Scores                               One-                                                                    reliability
                                                                                                                                                                                     One-way analyses of variance (ANOVA) were computed to examine reliability
                                                                                                                                                                                                                                             instructions.
                                                                                                                                                                                     coefficients for the PA and NA scales with timeframe instructions. In the first
Reliability generalization procedures were used in the present study to examine
                                                                  study                                                                                                                                                                            timeframe
                                                                                                                                                                                     analysis, PA reliability estimates were compared with eight timeframe
internal consistency estimates of the Positive Affect Negative Affect Schedule
                                                                  Affect                                                                                                             instructions. The assumption for homogeneity of variance was not violated
                                                  two-
(PANAS; Watson, Clark, & Tellegen, 1998), a two-factor measure for self-   self-                                                                                                     [Levene’
                                                                                                                                                                                     [Levene’s F(7, 100) = 1.915; p > .05]. Results indicated a statistically significant
reported mood. In addition, study characteristics that may impact score reliability
                                                              impact                                                                                                                                                                               post
                                                                                                                                                                                     difference, F(7, 100) = 3.629; p < .01, eta square = .203. A post hoc analysis was
were investigated. The mean reliability estimates for PA and NA scales were                                                                                                          computed to examine the difference among timeframe instructions. The Tukey
acceptable with both scales demonstrating negative skewness. In regard to study                                                                                                                                      year”
                                                                                                                                                                                     HSD post hoc indicated that “year” (M = .75; SD = .11) was significantly lower
characteristics, number of items correlated with PA and NA scale reliability                                                                                                                moment”                                 today”
                                                                                                                                                                                     than “moment” (M = .88; SD = .05; p < .01), “today” (M = .88; SD = .02; p <.01),
estimates. Finally, ANOVA results indicated that timeframe was significant in the
                                                                    significant                                                                                                             week”                                         weeks”
                                                                                                                                                                                     “past week” (M = .86; SD = .06; p < .05), “past few weeks” (M = .87; SD = .02; p <
level of score reliability for PA with “year” having the lowest score reliability.
                                        year”                                                                                                                                                         month”
                                                                                                                                                                                     .01), and “past month” (M = .86; SD = .03; p < .05) timeframes. No statistically
                                                                                                                                                                                                                               year”                days”
                                                                                                                                                                                     significant differences existed between “year” and “past few days” (M = .86; SD =
                                  Introduction                                                                                                                                                         general”
                                                                                                                                                                                     .04; p > .05) or “general” (M = .84; SD = .06; p > .05) timeframe instructions.
                                                                                                                          0 .70          0 .80       0 .90


Watson, Clark & Tellegen (1988) developed the Positive Affect Negative Affect                                             PA Reli abi li ty Coeffi ci ent                            Another ANOVA was computed to examine NA reliability estimates and      and
                                                                   Negative
Schedule (PANAS) validating a two factor measure for self-reported mood. Given                                                                                                                                                                      variance
                                                                                                                                                                                     timeframe instructions. The assumption for homogeneity of variance was not
                                                          self-
that the PANAS is a widely used measure in psychological research, evaluating             Figure 2: Boxplot of Negative Affect (NA) Reliability Scores                                        [Levene’                                                           difference
                                                                                                                                                                                     violated [Levene’s F(7, 87) = 1.329; p > .05]. No statistically significant difference
                                                               research,
the psychometric properties of its scores could increase the level of confidence in                                                                                                  was found, F(7, 87) = 0.601; p < .05, partial eta = .046.
                                                                level
                                                                   current
interpreting empirically based conclusions. The purpose of the current study is to
present a reliability generalization analysis across studies using the PANAS.
                                                             using                                                                                                                                                      Conclusion
While the theoretical and empirical support for the construct of is promising,
research surrounding score reliability remains to be established.
                                                       established.                                                                                                                  The objectives of the present study were to examine reliability estimates for the
                                                                                                                                                                                     PANAS using RG techniques and investigate study characteristics that may
                                   METHODS                                                                                                                                           influence score reliability. The mean reliability estimates for PA and NA scale was
                                                                                                                                                                                     acceptable with both scales demonstrating a negative skewness in the
A literature search was conducted in the PsychARTICLES and PsychINFO                                                                                                                                                                           characteristics,
                                                                                                                                                                                     distribution of reliability estimates. In regard to study characteristics, number of
                                                                   PsychINFO
databases using the terms positive and negative affect schedule and positive and                                                                                                                                                                     this
                                                                                                                                                                                     items correlated with PA and NA scale reliability estimates; this is not surprising
negative affect scale. Duplicated article were eliminating, resulting in a total of                                                                                                  given that score reliability tends to increase as the number of items increases (cf.
                                                            resulting
316 articles. An examination of these articles identified 59 articles did not use the                                                                                                                                                                  reliability
                                                                                                                                                                                     Cortina, 1993). Mean age also correlated negatively with PA reliability estimates.
                                                             articles
scale and 22 articles were written in non-English or were unavailable or unusable.
                                                                                                                  0 .70              0 .80           0 .90
                                                                                                                                                                                                                                                        level
                                                                                                                                                                                     ANOVA results indicated that timeframe was significant in the level of score
                                      non-
Of the remaining 235 articles, 62 (26.4%) did not report a reliability score and 74
                                                                                                                          NA Reli abi li ty Coeffi ci ent                                                                        year”
                                                                                                                                                                                     reliability for PA with consideration of “year” having the lowest score reliability.
                                                            reliability
(31.5%) induced a reliability score from another study. Cronbach alpha                    A correlation matrix including descriptive characteristics for variables in the study
                                                                                                                                                         variables                                                    REFERENCES
                                              test-
coefficients were reported in 94 studies and test-retest scores were reported in 5        is presented in Table 1. The correlation between the reliability coefficient and
                                            test-
studies. Because of the limited number of test-retest scores, only cronbach alpha         number of items was statistically significant for the PA scale (rxy = .45; p < .01)
                                                                                                                                                          (rxy                                                                              examination
                                                                                                                                                                                     Cortina, J. M. (1993). What is a coefficient alpha? An examination of theory and
estimates were used in the present study. Some articles provided reliability              and NA scale (rxy = .19; p < .05). In addition, the correlation between the PA
estimates for multiple samples, resulting in 140 coefficient alphas from the 94
                                                             alphas                                                                                                                                                                 78, 98-
                                                                                                                                                                                     application. Journal of Applied Psychology, 78, 98-104.
                                                                                                                                                      significant
                                                                                          reliability coefficient and mean age was also statistically significant (rxy = -.36; p <
articles.                                                                                 .01).                                                                                      Henson, R. K., & Thompson, B. (2002). Characterizing measurement error in
                                    RESULTS                                                                                                                                          scores across studies: Some recommendations for conducting “reliability
                                                                                                   Zero-
                                                                                          Table 1: Zero-Order Correlation Matrix of PANAS Reliability Scores and Study               generalization” studies. Measurement and Evaluation in Counseling and
                                                                                                                                                                                     generalization”
                                                                                          Variables                                                                                  Development, 35, 113-126.
For the positive affect (PA) scale, the mean reliability coefficient for the 133 cases
                                                         coefficient                                                                                                                                35, 113-
                                                                                                                                              PA α            NA α
reporting internal consistency reliability was .86 (SD = .06; SE = .005) with a 95%                                M              SD      Correlation Correlation
confidence interval ranging from .85 to .87. The median and mode reliability                                                                                                         Watson, D., Clark, L. A., & Tellegen, A. (1988). Development and validation of
                                                                                                Number of                                                                                                                                       scales.
                                                                                                                                                                                     brief measures of positive and negative affect: The PANAS scales. Journal of
                                                                  from
coefficient were .88 and .89 respectively, with scores ranging from .62 to .96. The                items          9.42           1.59         .45**           .19*
PA distribution was negatively skewed (-2.05; SE = .210) with a kurtosis of 5.63                                                                                                                                         54, 1063-
                                                                                                                                                                                     Personality and Social Psychology, 54, 1063-1070.
                                          (-                                                   Sample size      253.67          321.45         -.10            .09
                                                             reliability
(SE = .417). For the negative affect (NA) scale, the mean reliability coefficient for            Mean age        35.05           19.50        -.36**           -.11
the 119 cases reporting internal consistency reliability was .84 (SD = .05; SE =               Percent male      38.36           26.95         -.01            -.18
.005) with a 95% confidence interval ranging from .83 to .85 The median and                       Percent
mode reliability coefficient were .85 and .87 respectively, with scores ranging from            Caucasian        67.04           32.52         -.05            -.07
                                                          (-
.67 to .95. The NA distribution was negatively skewed (-.98; SE = .222) with a
kurtosis of 1.10 (SE = .440). See Figures 1 and 2 for boxplots of PA and NA
                                                                   of                          Note. * p < .05, ** p < .01
reliability scores.

				
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