[Validation of ESCAP-CD as an instrument of measure for the evaluation of the quality of life in prostatic cancer. Part 2a].
In order to make a measure of quality of life related to health (QLRH) useful in the investigation, it must fulfill the psychometric properties (validity, reliability and sensibility). The selection of an instrument is a job for the clinic that must choose the most effective for each proposed objective. We set out the objectives to validate the ESCAP-CDV in a multicentric study in Andalusia. We studied 88 patients who were submitted to the instrument presented to validation and two more tests recognized already: the QLQ-C30 from EORTC gold standard in Europe in the valuation of the neoplastic patients' quality of life and the KARNOFSKY the most clinic utility index in neoplastic patients, used to correlate the items.


RESULTS
Questionnaire acceptance analysis: The difficulty of understanding was greater for QLQ C30 items (6.81%) than ESCAP items (1.98%). The lapse of time needed to carry out the test was shorter in the ESCAP test (9.84 min) than in the QLQ C30 (13.13), test. Structural analysis or internal validity analysis: The homogeneity index of the items is high (alfa of Cronbach = 0.93). The dimensionality proposed is not accepted, due to the existence of some modifications pund in the factorial analysis. Finally, the established dimensions: Physical and Emotional Capacity (PEC), 5 items; General Symptoms (GS), 4 items; Pain (P), 3 items; Ligh Functional Capcity (LFC), 4 items; Serious Functional Capacity (SFC), 2 items; Economic State (ES), 3 items; Social and Family State (SFE), 5 items; Capacity Sexual (CSX), 2 items; Isolated Variables (IV), 2 items; and Specific Questionnaire (P), 6 items. The ESCAP is a scale with a normal distribution. Approach or external validity analysis: The ESCAP test is well correlated with the other two scales. Reliability test retest: The interclass correlation coefficient is 0.94 in the ESCAP, not so in the KARNOFSKY that is 0.77.


CONCLUSIONS
The ESCAP-CDV is a new instrument of valuation of the QLRH composed of a general questionnaire and other specific test of prostate cancer. It has turned out to be a very homogeneous scale due to its internal consistence (alfa of Cronbach of 0.93), showing that it has a normal distribution, that correlates correctly with the scales compared and it is a valid scale to measure the prostate cancer patients' quality of life. The ESCAP-CDV has shown to be a scale with a high reliability (0.94), setting up as an instrument not only useful for investigation, but to clinical use, as well.
Morales López
A
A
Servicio de Urología, Hospital Universitario Virgen del Rocío, Sevilla.
Grau Fibla
G
G
Campoy Martínez
P
P
Benavente Rodríguez
A
A
Pascual del Pobil Moreno
J L
JL
D006801:Humans; D017567:Karnofsky Performance Status; D008297:Male; D011471:Prostatic Neoplasms / Q000523:psychology; D011788:Quality of Life; D011795:Surveys and Questionnaires