Life satisfaction is one of the most important indicators for mental health evaluation. The assessment of life satisfaction in Iranian elderly people is a must, so this study was carried out in order to assess the reliability and validity of the 13 item LSI-Z questionnaire in Kashan -Iran 2007.

The 13 item LSI- Z English Version was translated to Persian. demographic data and a question about total life satisfaction status was also assessed .The sampling was performed using convenience method. people aged ≥60 years old who conferred to health centers in kashan city in spring 2007 (n=75) were selected. After their consent informed, the questionnaires were completed. Reliability was determined via internal consistency using item-total correlation; cronbach's alpha and split-half. Construct validity was determined through known-groups approach; the samples were divided into 5 groups depend on their answers to the total life satisfaction status question, and then life satisfaction index-z scores were compared among 5 groups. The data were analyzed using pearson correlation coefficient, unequal spearman brown, Guttman, Cronbach's alpha coefficient and one-way ANOVA.

In 0-26 Scale, life satisfaction score was 13/68±5/47. The questionnaire reliability coefficient was 0/78-0/79. Item-total correlation confirmed its reliability too. LSI-Z scores were significantly different among the 5 known- groups (p=0/0001, f = 121/66); so the known-groups approach revealed that this tool is valid.

the 13 item LSI-Z Persian version for evaluation of life satisfaction in Iranian elderly people is valid and reliable.