* Percentile Ranks: The most common and arguably most meaningful way to interpret scores is by comparing them to a normative sample. If you have access to the norms provided with the scale (or a comparable study using the same scale), you can determine a teacher's percentile rank. This indicates how their score compares to the scores of other teachers in the sample. For example, a teacher in the 90th percentile would be considered to have high efficacy relative to the norm group. Those in the 10th percentile or below would be considered low.
* Standard Scores: Some analyses might use standard scores (like z-scores) instead of percentile ranks. A positive z-score indicates a score above the average, and a negative z-score indicates a score below average. The magnitude of the z-score reflects the distance from the mean. Again, there's no magic number, but a generally accepted approach might be to consider those significantly above or below the mean (e.g., |z|>1.5) as high or low efficacy, respectively.
* Comparison to Colleagues: Within a specific school or district, you could compare individual teacher scores to the average score of their colleagues. This provides a contextualized understanding of efficacy relative to their immediate working environment, though it lacks the broader comparison offered by normative data.
* Consider the Subscales: The Gibson and Dembo scale typically has subscales (often focusing on personal efficacy and outcome expectancy). Analyzing performance on each subscale separately can offer a more nuanced understanding of a teacher's efficacy profile. A teacher might have high personal efficacy but low outcome expectancy, for instance.
In summary: There is no single score that defines high or low teacher efficacy. The best approach uses the provided norms to calculate percentile ranks or standard scores. These allow for comparison to a larger group of teachers and provide a more statistically robust interpretation. Without access to normative data, comparing teachers within a single context (like a school) is the next best option, although this lacks external validity. Remember to always consider the subscales for a more comprehensive picture.