Development and psychometric testing of the Cancer Knowledge Scale for Elders.
OBJECTIVE
To develop the Cancer Knowledge Scale for Elders and test its validity and reliability.


BACKGROUND
The number of elders suffering from cancer is increasing. To facilitate cancer prevention behaviours among elders, they shall be educated about cancer-related knowledge. Prior to designing a programme that would respond to the special needs of elders, understanding the cancer-related knowledge within this population was necessary. However, extensive review of the literature revealed a lack of appropriate instruments for measuring cancer-related knowledge. A valid and reliable cancer knowledge scale for elders is necessary.


METHODS
A non-experimental methodological design was used to test the psychometric properties of the Cancer Knowledge Scale for Elders.


METHODS
Item analysis was first performed to screen out items that had low corrected item-total correlation coefficients. Construct validity was examined with a principle component method of exploratory factor analysis. Cancer-related health behaviour was used as the criterion variable to evaluate criterion-related validity. Internal consistency reliability was assessed by the KR-20. Stability was determined by two-week test-retest reliability.


RESULTS
The factor analysis yielded a four-factor solution accounting for 49.5% of the variance. For criterion-related validity, cancer knowledge was positively correlated with cancer-related health behaviour (r = 0.78, p < 0.001). The KR-20 coefficients of each factor were 0.85, 0.76, 0.79 and 0.67 and 0.87 for the total scale. Test-retest reliability over a two-week period was 0.83 (p < 0.001).


CONCLUSIONS
This study provides evidence for content validity, construct validity, criterion-related validity, internal consistency and stability of the Cancer Knowledge Scale for Elders. The results show that this scale is an easy-to-use instrument for elders and has adequate validity and reliability.


CONCLUSIONS
The scale can be used as an assessment instrument when implementing cancer education programmes for elders. It can also be used to evaluate the effects of education programmes.
Su
Ching-Ching
CC
Chung Jen College of Nursing, Health Science and Management, Chia Ti City, Taiwan, ROC.
Chen
Yuh-Min
YM
Kuo
Bo-Jein
BJ
D000368:Aged; D000369:Aged, 80 and over; D005163:Factor Analysis, Statistical; D005260:Female; D015438:Health Behavior; D007722:Health Knowledge, Attitudes, Practice; D006801:Humans; D008297:Male; D009369:Neoplasms / Q000175:diagnosis / Q000451:nursing / Q000517:prevention & control*; D010353:Patient Education as Topic / Q000592:standards; D011594:Psychometrics; D015203:Reproducibility of Results; D013223:Statistics as Topic; D011795:Surveys and Questionnaires / Q000592:standards*