3.2. Measure
Ageism Scale: Vefikuluçay Yilmaz and Terzioğlu developed the original version of the ageism scale. This scale comprises 23 items to measure three dimensions, including negative attitude towards aging (score range: 23 - 53), neutral attitude towards aging (score range: 54 - 84), and positive attitude towards aging (score range: 85 - 115). The items are scored on a 5-point Likert scale, with response options ranging from "completely agree" (scored as 5) to "completely disagree" (scored as 1). The Cronbach’s alpha coefficients for the positive, restricting, and negative attitudes sub-scales were 0.70, 0.70, and 0.67, respectively (
11).
Demographic information: This checklist comprises information about various demographic factors, such as age, gender, ethnicity, religion, marital status, level of education, occupation, monthly income, and the presence of an older adult.
3.3. Participants, Procedures, and Translation
In this study, we followed the international quality of life assessment (IQOLA) principles (
18) to translate the Ageism Scale from English to Persian. First, two translators performed a forward translation, and any discrepancies were resolved in a meeting. The unified translated version was then back-translated by two bilingual authors, and the backward translations were compared to the original English version. Two geriatricians reviewed the final Persian-translated version of the questionnaire and provided feedback to enhance its clarity (
Figure 1, stage one).
Both qualitative and quantitative approaches were used to determine face validity. A total of 12 individuals from the target population and eight experts in relevant fields were invited to participate. Necessary modifications were made based on their feedback. The language and style of the text were revised by a professional scientific editor to enhance scientific rigor (
Figure 1, stage two).
Two indicators, the content validity ratio (CVR) and the content validity index (CVI), were used for the quantitative content validity assessment. The CVR was used to assess the necessity of an item, and the CVI was used to assess the relevance of each item. A total of 14 social work, social welfare, sociology, and geriatrics experts were recruited to evaluate each item based on a three-part score ((1) not necessary; (2) useful but not necessary; (3) necessary). The CVR was calculated to determine the importance and priority of each item. This process ensured that the most essential and appropriate content was included in the questionnaire.
The language and style of the text were revised by a professional scientific editor with expertise in the relevant field to enhance the scientific rigor of the study (
Figure 1, stage two).
The exploratory factor analysis (EFA) and confirmatory factor analysis (CFA) were conducted on a sample of 230 participants to assess the structural validity of the Persian version of the Ageism Scale. The participants were selected based on inclusion criteria and convenient sampling. The KMO measure and Bartlett’s test of sphericity were used for the EFA. The KMO measure shows the adequacy of the sample size for the analysis, with a range of zero to one, and a value of at least 0.5 is considered significant (
19). Bartlett’s test was used to ensure the data suitability and a significance level of 0.05 was considered significant. A sample of 230 participants was also selected for the CFA based on inclusion criteria and convenient sampling. Multivariate techniques were used to examine the relationships between variables. Several indicators, including the squared multiple correlations (SMC), the squared SMC divided by degrees of freedom, the root-mean-square error of approximation (RMSEA), the goodness of fit (GIF) index, the normed fit (NFI) index, and the comparative fit index (CFI), which are commonly used in CFA were used to evaluate the model fit (
10,
19). An exploratory factor analysis was conducted on 230 participants in the sample. The KMO measure was used to ensure the adequacy of the sample size, and Bartlett’s test of sphericity was used to confirm the suitability of the data. A sample of 230 participants was also included for the confirmatory factor analysis, and multivariate techniques were used to assess the relationships between variables. Several fit indicators were used to evaluate the model fit, including the SMC, squared SMC divided by degrees of freedom, RMSEA, GIF, NFI, and CFI. The adequacy of the sample size was confirmed by the KMO measure, which ranges from zero to one, with a value of at least 0.5 considered significant. Bartlett’s test was used to ensure the suitability of the data, and a significance level of 0.05 was considered significant. The fit indicators were used to examine the fit in the confirmatory factor analysis (
10,
19) (
Figure 1, stage three).
A test-retest method and intra-cluster correlation coefficient (ICC) were used on 40 participants who were asked to respond to the Persian version of the Ageism Scale at two different time points with a two-week interval to determine the reliability. The ICC test was considered the most acceptable for establishing the instrument’s stability. The internal consistency of the questionnaire was calculated using Cronbach’s alpha coefficient for the entire questionnaire and each item separately (
10). Then, the reliability of the structure was calculated by examining the variance ratio of observed variables to latent variables in the confirmatory factor analysis. The stability of the factors, or the reliability of the structure, is an alternative to Cronbach’s alpha coefficient in the structural equation modeling analysis. This study considered the stability of over 0.7 acceptable (
19). This study used SPSS version 23 (Armonk, NY: IBM Corp) and AMOS version 5 for data analysis. This study is part of a research project on ageism in Iran, which was approved by the Medical Ethics Committee of the Mashhad University of Medical Sciences under the code IR.MUMS.REC.1399.631.
This study followed the IQOLA principles (
20) to translate the Ageism Scale from English to Persian. First, two expert translators performed a forward translation, and any discrepancies were resolved in a meeting. The unified translated version was then back-translated by two bilingual authors. The backward translations were compared to the original English version. Two geriatricians reviewed the final Persian-translated version of the questionnaire and provided feedback to enhance its clarity (
Figure 1, stage one).
Both qualitative and quantitative approaches were used to determine face validity. A total of 12 individuals from the target population and eight experts in relevant fields were invited. Necessary modifications were made based on their feedback. A professional, scientific editor revised the language and style of the text to enhance scientific rigor (
Figure 1, stage two).
The CVR and CVI were used to examine content validity. A total of 14 experts assessed each item based on a three-part score, and the CVR and CVI were calculated to determine the importance and relevance of each item. Exploratory and confirmatory factor analyses were conducted to assess structural validity, with several fit indicators to evaluate the model fit. The reliability was determined using a test-retest method and intra-cluster correlation coefficient, with Cronbach’s alpha coefficient used to calculate internal consistency. The Medical Ethics Committee of the Mashhad University of Medical Sciences approved the study, and the data were analyzed using SPSS version 23 and AMOS version 5 (
Figure 1, stage three). This study is part of a research project on ageism in Iran.