The development of the measurement of Presence Scale
This exploratory study utilized a methodological design based on correlational methods to estimate initial reliability and construct validity of the Measurement of Presence Scale (MOPS). Paterson and Zderad's conceptualization (1976) of the humanistic nursing situation provided the frame of reference. Attributes which related to the essential structure of presence were identified and defined through systematic theory analysis and construction.
Using measurement theory and strategies items were generated and a self-report interval level, norm referenced scale was developed. Content validity was estimated by a panel of experts and the scale was resized from 135 items to 60 items. Initial estimates of internal consistency were obtained in a pilot study.
Three hundred twenty-four Registered Nurses participated in the major study to estimate internal consistency reliability and construct validity of the scale. The internal consistency reliability (Cronbach's Alpha) for the total scale was 0.9324. The subscale alpha correlation coefficients were all greater than.60.
Factor analysis procedures produced nine mutually exclusive subscales which met predetermined criteria. Interpretation of the produced subscales was accomplished. The following subscales were interpreted as a result of the analysis: (1) valuing/attending to self and others, (2) connecting, (3) transacting, (4) enduring memory from the past, (5) engaging for growth, (6) encountering, (7) availability, (8) person or event sustaining memory, and (9) disclosing and enclosing.
Item analysis on the original Measurement of Presence Scale (MOPS) between the upper and lower quartile groups by subscale score and total score revealed that three items did not discriminate significantly.
Designated subscales showed a moderate to high correlation between the subscales and the total Measurement of Presence Scale (MOPS) and were significant at the 0.01 level. These findings provide support for the initial estimations of internal consistency and construct validity of the scale. Further cumulative testing is recommended.