Measurement of source credibility has been a concern of the Communication discipline for over 40 years. The first multidimensional measure appeared in the Communication literature in 1966 (McCroskey, J .C., Scales for the measurement of ethos, Speech Monographs, 33, 65-72) and provided scales measuring competence and trustworthiness. Many other studies were conducted over the next 30 years. The most complete measure (reported below) includes scales for three dimensions: competence, trustworthiness, and goodwill/caring. These are measures of constructs which are parallel to those theorized by Aristotle in The Rhetoric.

The development of these measures employed oblique factor analyses which generated correlated dimensions. That is, the three measures represent unique constructs, but those constructs are intercorrelated, as suggested by Aristotle and found in many research studies. Earlier work had used orthogonal factor analyses which forces uncorrelated factors. Thus, the new measures are more consistent with general rhetorical\social influence theories as well as previous findings. These measures provide three separate total scores, one for each dimension. THESE SCORES SHOULD NOT BE SUMMED TO CREATE A SINGLE SCORE. To do so would be adding the proverbial apples and oranges (and watermelons). They should not be employed in stepwise regression analyses because their colinearity will violate the assumptions of this statistical procedure. However, they can be used in regular multiple regression and in canonical correlational analyses, as well as for computing individual simple correlations. 

The alpha reliabilities of these measures usually range between .80 and .94.

Instructions: On the scales below, indicate your feelings about your manager (or, if not currently employed, your most recent supervisor).Numbers 1 and 7 indicate a very strong feeling. Numbers 2 and 6 indicate a strong feeling. Numbers 3 and 5 indicate a fairly weak feeling. Number 4 indicates you are undecided. 

1)                        Intelligent 1 2 3 4 5 6 7 Unintelligent

2)                          Untrained 1 2 3 4 5 6 7 Trained 

3)                Cares about me 1 2 3 4 5 6 7 Doesn't care about me

4)                              Honest 1 2 3 4 5 6 7 Dishonest

5) Has my interests at heart 1 2 3 4 5 6 7 Doesn't have my interests at heart

6)                     Untrustworthy 1 2 3 4 5 6 7 Trustworthy 

7)                              Inexpert 1 2 3 4 5 6 7 Expert 

8)                      Self-centered 1 2 3 4 5 6 7 Not self-centered 

9)           Concerned with me 1 2 3 4 5 6 7 Not concerned with me

10)                       Honorable 1 2 3 4 5 6 7 Dishonorable

11)                          Informed 1 2 3 4 5 6 7 Uninformed

12)                                Moral 1 2 3 4 5 6 7 Immoral

13)                      Incompetent 1 2 3 4 5 6 7 Competent 

14)                           Unethical 1 2 3 4 5 6 7 Ethical 

15)                         Insensitive 1 2 3 4 5 6 7 Sensitive 

16)                                Bright 1 2 3 4 5 6 7 Stupid

17)                                Phony 1 2 3 4 5 6 7 Genuine 

18)             Not understanding 1 2 3 4 5 6 7 Understanding 
 

SCORING:To compute your scores, add your scores for each item as indicated below: 

Recode BOLDED questions with the following format:

1=7 

2=6 

3=5 

4=4 

5=3 

6=2 

7=1 

Competence Factor (1, 2, 7, 11, 13, and 16)__________ 

Caring/Goodwill Factor (3, 5, 8, 9, 15, and 18)__________ 

Trustworthiness Factor (4, 6, 10, 12, 14, and 17)__________

Source: 

McCroskey, J. C., &Teven, J. J. (1999).Goodwill: A reexamination of the construct and its measurement. Communication Monographs, 66, 90-103.