Development and Psychometric Properties of Sexual and Reproductive Health Literacy Instrument for Infertile Women (SRH-Life): A Mixed Method Study

Background: Promoting sexual- reproductive health literacy is one of the most important strategies for achieving the goals of sexual- reproductive health in different groups of women. Infertile women are one of the most vulnerable groups to the adverse effects of low levels of health literacy. Since no specic instrument exists for assessing the level of sexual- reproductive health literacy, therefore, this study aimed to develop and evaluate the psychometric characteristics of an instrument for measuring sexual and reproductive health literacy among infertile women (Sexual and Reproductive Health Literacy instrument for infertile women: SRH-Life). Methods: This was a mixed method study with exploratory design which conducted from July 2018 to Jan 2020 in northern Iran. Semi structured interviews with infertile women, literature review and, expert panel comments were utilized to generate an item pool. Then, the psychometric properties of the instrument, validity and reliability were assessed. Results: The initial instrument contained 78 items. Next, 10 experts evaluated content validity. Some items were removed and a provisional version of the instrument with 47 items was provided. Then, the face validity was performed by 10 infertile women. Finally, a random sample of 235 infertile women completed the instrument and construct validity were assessed. The exploratory factor analysis was performed, 35 items were loaded, which indicated a 4-factor solution for the instrument including reproductive health information (8 items), infertility and treatment information (9 items), sexual health information (8 items) and functional sexual- reproductive literacy (10 items) that jointly explained 55.3% of the variance observed. For reliability, internal consistency showed satisfactory results with Cronbach’s alpha coecients ranging from 0.89 to 0.9. Intraclass correlation coecient (test-retest analysis) showed acceptable stability for the instrument. Conclusion: The results showed that Sexual and Reproductive Health Literacy instrument for infertile women (SRH-Life) is a valid and reliable measure for assessing sexual and reproductive health literacy among women with infertility. sequential The present study is the rst study to design and assess the psychometric properties an instrument for measuring sexual and reproductive health literacy in women with infertility. The initial instrument was designed based on data from a qualitative study of infertile women, expert opinions, and extensive literature review on health literacy. The designed instrument includes a range of questions to assess reproductive health literacy and sexual health literacy. The results showed that the SRH-Life is a valid instrument for measuring sexual and reproductive health literacy among women with infertility. Also, the multidimensional structure of the designed questionnaire is one of its strengths. The questionnaire consists of 35 questions and is developed in 4 dimensions, including reproductive health information, infertility and treatment information, sexual health information, and sexual- reproductive functional literacy, which are completed as self-administrating. Because most participants completed the questionnaire within 15 minutes, the questionnaire could be easily used for screening. One of the strengths of this instrument is that by removing the dimension of "Infertility and Treatment Information" consisting of 9 items and removing an item related to infertility (Question 29) related to the dimension of functional literacy, it can be used as an instrument to measure sexual- reproductive health literacy in women of reproductive ages (consisting of 25 questions).

evaluation of sexual and reproductive health literacy instrument in women with infertility in Iran, so that it can be used as a basis for evaluating, improving and promoting sexual and reproductive health literacy in women with infertility.

Methods
The present study is a sequential exploratory mixed method study of instrument development variant, which was conducted in the infertility centers in the city of Rasht (in the North of Iran) from July 2018 to Jan 2020. The present study was conducted in two stages, the qualitative stage for Item generation and the quantitative stage for measuring the psychometrically evaluate an instrument.

Stage 1: Item generation
Qualitative study and a literature review were used to generate an item pool. A qualitative study with a conventional content analysis approach was conducted with the aim of exploring the understanding and experiences of women with infertility of the concept of sexual-reproductive health literacy. Purposive sampling was performed with maximum diversity in terms of age, education, employment status, socialeconomic status, cause of infertility and duration of infertility. Criteria for entering the study included Iranian women with primary and secondary infertility, willing to participate in research, able to understand, speak, communicate and interview in Persian. Specialized infertility centers in the city of Rasht (a city in northern Iran) were the setting of data collection. In-depth and semi-structured interviews with women with infertility and key informants were conducted individually and face-to-face in a private room at the Infertility Center. Sampling continued until the data was saturated, so that no new data from the interviews were obtained. Interviews were audio recorded with participants' permission. The duration of each interview varied from 30 to 90 minutes and averaged 45 minutes. Then, in the shortest possible time, after listening to the text of the interview several times, the interviews were transferred word for word on paper and nally typed. Data were analyzed by conventional content analysis. At this stage, items pool was extracted by inductive approach, based on the concepts explored in the content analysis of the qualitative study. Then, to complete the items using a deductive approach, all published studies in databases of Pubmed, Web of Science, ProQuest, MEDLINE, Google Scholar and dedicated sites of WHO and CDC were searched from 2000 to 2019 and different combinations of keywords, including sexual health, reproductive health, health literacy, women, infertility, questionnaire, validity, reliability, psychometric assessment, Qualitative/Mixed Method Studies were used. Therefore, using the inductivedeductive approach, the initial instrument of reproductive and sexual health literacy was designed and entered the second stage to evaluate psychometric properties.

Stage 2: psychometric properties assessment
At this stage of the study, content validity, face validity and construct validity were examined. Also, instrument reliability was assessed in terms of internal consistency and stability.

Content validity
Content validity was assessed in two quantitative and qualitative methods with the help of an expert panel consisting of 10 experts in the eld of reproductive and sexual health, health promotion, health literacy and psychometrics. The validity of the qualitative content was examined in terms of the content of the items, the general structure of the questionnaire, the need to remove or add items, the appropriate position of items, the use of appropriate words, compliance with grammar and proper scoring of items.
Quantitative content validity was assessed by calculating the content validity ratio (CVR) and content validity index (CVI). To assess content validity by CVR, 10 experts were asked to evaluate each item of the questionnaire according to a 3-point scale (necessary, useful but not necessary, not necessary) and the CVR was calculated for each item. According to Lawshe's table, items with CVR > 0.62 (based on 10 experts' evaluation) were kept [17].
To determine the content validity index (CVI), the opinions of 10 experts were examined to determine the relevance, clarity, and simplicity of each item according to the Waltz & Bausell content validity index [18]. This index was evaluated in a 4-point Likert scale (very relevant, relevant, relatively relevant, and not relevant). If the score of the content validity index was higher than 0.79, the item was considered appropriate [19].

Face validity
To determine the face validity of the instrument, 10 individuals of women with infertility were selected using a purposive sampling to verify the clarity, relevance and di culty of each item.

Construct validity
To perform construct validity, 235 women with infertility completed the questionnaire. Participants were available through infertility clinics and they were recruited directly. The sample size was determined as the number of items in the instrument (47 items) multiplied by 5 [20]. At this stage, convenience sampling was used and the criteria for entering the study included women with primary and secondary infertility, a willingness to participate in the study, and a minimum of literacy. First, demographic data and participants' infertility status were recorded. Then, the questionnaires, in the form of a 5-point Likert scale, were completed as Self-administered. The data were collected by the researcher, and when the questionnaire was delivered, the researcher reviewed it so that no question remained unanswered. After entering the data, SPSS 23 software was used for statistical analysis.
In the present study, the construct validity was examined using Exploratory Factor Analysis (EFA) with varimax rotation with the aim of identifying the dimensions of the questionnaire. The Kaiser Meyer-Olkin (KMO) and Bartlett's Test of Sphericity were performed to determine the appropriateness of the sample for factor analysis [21,22]. Eigenvalues above 1 and factor loadings greater than or equal to 0.30 were considered appropriate to verify the number of possible underlying factors. To achieve the most desirable number of factors, the share of total variance expressed, scree plot and eigenvalue, were considered.

Reliability
In this study, the reliability of the questionnaire was assessed by examining the internal consistency and repeatability. To examine the internal consistency, Cronbach's alpha coe cient (acceptable level of above 0.7) was calculated for each dimension and the whole scale [23]. To assess the questionnaire's time stability, the Intraclass Correlation Coe cient (ICC) was calculated by performing test-retest analysis. For this purpose, 20 infertile women completed the questionnaire twice in 2-week intervals. The ICC of 0.75 or higher were considered satisfactory [24].

Ethical considerations
This study was approved by the Ethics Committee of Faculty of Nursing and Midwifery of Tehran University of Medical Sciences (ethics code:IR.TUMS.FNM.REC.1397.066). A written consent letter was obtained from all participants and interviews were conducted in a private room in the infertility centers. Maintaining anonymity and con dentiality of the data were collected and analyzed.

Results
Qualitative data were obtained through 19 in-depth and semi-structured interviews, including interviews with 16 women with infertility and 3 key informants (1 gynecologist and infertility specialist, 2 counseling midwives of the infertility Center). Infertile women in this study ranged in age from 27 to 44 years. Of the 16 women with infertility, 11 had primary infertility and 5 had secondary infertility. The texts were read several times to get a general concept. The meaning units were identi ed and then the related ones were compressed and achieved codes. Codes were categorized into categories and subcategories. Finally, 6 themes (reproductive health information needs, sexual health information needs, information seeking, understanding, validating and consciously using information) emerged.
In total, from the results of the content analysis of the interviews (165 items) and extensive literature review (4 items), items pool, consisting of 169 items, was compiled. After reviewing and merging the overlapping items by the research team, the initial instrument with 78 items was designed. Then, the 78item instrument designed to check the content validity, face validity, construct validity and reliability entered the second stage.

Content validity
In qualitative content validity, comments and recommendations of 10 reproductive and sexual health experts were performed. The modi cations were implemented at this phase of assessment that the most important of which was the separation of long items and simpli cation of item. Therefore, by separating the items, 2 items were added to the questionnaire. Then, the 80-item questionnaire was completed by 10 experts for assessment of CVR and CVI. The minimum accepted CVR score on the Lawshe table was 0.62. Accordingly, 33 items were removed and nally 47 items remained to enter the next stage to determine the CVI. By assessment CVI, all items received an acceptable score and no items were removed. Also, the average of scores for content validity index (S-CVI/Ave) was calculated and the score was 0.965, which was acceptable considering that its value is higher than the standard value of 0.9.

Face validity
To assess the face validity, 10 women with infertility were selected using a purposive sampling to verify the clarity, relevance and di culty of understanding each item. Therefore, 7 items was reworded or modi ed, and the questionnaire entered the stage of construct validity with 47 items.

Construct validity
Exploratory factor analysis was performed on data from 235 infertile women, of whom 63.4% had primary infertility and 36.6% had secondary infertility. The average age of the participating women was 30.8 ± 6.1 with a range of 20 to 48 years; The average duration of marriage was 7.8 ± with a range of 1 to 30 years and the average duration of infertility was 4.5 with a range of 1 to 28. Table-1 shows the characteristics of the participants.
The adequacy of sample size was con rmed by Kaiser-Meyer-Olkin (KMO) and Bartlett's Test of Sphericity (KMO = 0.945 and χ2 = 5687.244, p = 0.000). The results showed that the correlations between items were large enough to perform exploratory factor analysis.
The initial analysis indicated a 6-factor solution with eigenvalues greater than 1 that jointly accounted for 59.4% of the variance observed. After assessment, two factors were excluded for the following reasons: a. There was factor 6 with two items more relevant to sexual health information and thus the factor was excluded and the items conjugated to factor 2 (sexual health information).
b. Item loading on factor 5 did not satisfy the expected threshold. 3 items with low loading were relevant to infertility but Item loading on factor 1 (infertility and treatment information) satis ed the expected threshold.
Finally, based on the exploratory factor analysis using Maximum Likelihood method, the questionnaire items were placed in 4 factors with eigenvalues greater than 1, that jointly accounted 55.34% of the total variance. The factor loading of each item in the factor matrix and the rotated matrix was considered to be at least 0.3. Accordingly, 12 items were removed and the number of items was reduced from 47 items to 35 items. Eventually, a sexual-reproductive health literacy questionnaire was designed in infertile women with 35 items on 4 factors including reproductive health information (8 items), infertility and treatment information (9 items), sexual health information (8 items) and functional reproductive-sexual literacy (10 items). Table-2 shows the factor loading of the items after rotation and in the relevant domains.

Reliability
Reliability of the questionnaire was assessed by estimating the Cronbach's alpha coe cient. The results showed that all factors had acceptable internal consistency. The Cronbach's alpha coe cient for each subscale and the questionnaire as a whole ranged from 0.89 to 0.91. The time stability of the questionnaire and its sub-scales as measured by the ICC was found to be satisfactory (ranges from 0.82 to 0.94) and they were above acceptable threshold (Table-3).

Discussion
The present study is the rst study to design and assess the psychometric properties an instrument for measuring sexual and reproductive health literacy in women with infertility. The initial instrument was designed based on data from a qualitative study of infertile women, expert opinions, and extensive literature review on health literacy. The designed instrument includes a range of questions to assess reproductive health literacy and sexual health literacy. The results showed that the SRH-Life is a valid instrument for measuring sexual and reproductive health literacy among women with infertility. Also, the multidimensional structure of the designed questionnaire is one of its strengths. The questionnaire consists of 35 questions and is developed in 4 dimensions, including reproductive health information, infertility and treatment information, sexual health information, and sexual-reproductive functional literacy, which are completed as self-administrating. Because most participants completed the questionnaire within 15 minutes, the questionnaire could be easily used for screening. One of the strengths of this instrument is that by removing the dimension of "Infertility and Treatment Information" consisting of 9 items and removing an item related to infertility (Question 29) related to the dimension of functional literacy, it can be used as an instrument to measure sexual-reproductive health literacy in women of reproductive ages (consisting of 25 questions).
Measuring health literacy is essential to prevent of the dangers of limited literacy by awareness and or designing speci c interventions to increase it [25]. Since the introduction of health literacy, researchers have developed a variety of tools for measuring health literacy, the most widely used of which are the rapid estimate of adult literacy in medicine (REALM) 6 test of functional health literacy in adults (TOFHLA) 7 , and the newest vital sign (NVS) 8 [26]. Most health literacy studies examine general health literacy and do not focus on speci c areas [27].
Women's sexual-reproductive health literacy is a new topic and although many studies have identi ed health literacy in women's reproductive health as important [28], few studies have been conducted in this area. In this regard, Masoumi et al. (2019) designed an instrument for measuring the sexual health literacy of Iranian adults (men and women over the age of 18) that included 40 questions in 4 dimensions including access (7 items), reading and comprehension (18 items), evaluation and analysis (5 items), information usage (10 items) and literature review was used to design the initial items of the instrument [29]. Sexual health literacy for adults (SHELA) questionnaire, like most health literacy instruments, including health literacy assessment instruments in Iranian adolescents [30], health literacy instruments for married immigrant women in South Korea [31] and health literacy instruments for women with breast cancer [32] were designed based on the dimensions of health literacy. Dimensions of access, understanding, evaluation and judgment, decision-making and behavior are the main foundations of health literacy in de nitions [33]. In the present instrument, the domain of functional sexual-reproductive literacy consisting of 10 items examines women's ability to access and search, understand and evaluate, evaluate and use the information of sexual-reproductive health.
The questions of the present instrument were extracted from a qualitative study based on in-depth interviews, during the factor analysis, the dimensions of reproductive health information, infertility and treatment information and sexual health information were obtained, which can examine the knowledge and the most important information needs of reproductive and sexual in women with infertility. Compared to other studies, the factor analysis structure in the present instrument has a more diverse range and due to the presence of more than 3 items in each factor, it has a more stable and reliable structure [34]. (2012) proposed 5 steps in the designed model of Health Literacy Road, the rst step of which was health knowledge, so that a person's basic knowledge of health and health concerns is formed through reading, interacting with health professionals or health care providers, discussing with friends and family, and providing health information from the media, and the individual can increase health knowledge in the later stages by developing health literacy skills and practices, including information seeking, comprehension, etc., and ultimately lead to conscious decision-making and appropriate action [38].
Health literacy is the individual, cognitive, and social skills that determine a person's ability to access, understand, and use information to maintain and promote desired health and improve knowledge and understanding of health components and change attitudes and motivations related to health behavior and improve self-e cacy in relation to certain tasks [39]. Therefore, by recognizing the dimensions of sexual-reproductive health in women through a special and comprehensive instrument, health care providers and specialists can provide the required information in accordance with the facilities and understanding of women. As a result of better interaction with health care providers, women's participation in the decision-making process of treatment and self-care methods will lead to optimal treatment outcomes and the promotion of women's sexual and reproductive health.

Limitations:
To measure how valid of instrument, it is necessary to compare the results of measurements with other recognized instruments. Therefore, it is recommended that concurrent or criterion validity of the instrument be investigated in future studies. Also, the instrument was tested in one location using a cross-sectional approach and stability (test-retest analysis) was examined in a separate sample.

Conclusion
The Sexual and Reproductive Health Literacy instrument for infertile women (SRH-Life) is a valid and reliable instrument that, in addition to assessing the level of sexual and reproductive health literacy that can identify the information needs and barriers to promoting sexual and reproductive health literacy in infertile women so that planning and necessary interventions can be done accordingly. It is also a short and easy-to-use instrument that is suggested for assessing the level of sexual and reproductive health literacy of women with infertility in future studies. In addition, it is possible that by eliminating infertility and treatment information dimension, it could be used to assess sexual and reproductive health literacy in other women of reproductive ages. Because this instrument examines the most important issues of sexual and reproductive health in women. Maintaining anonymity and con dentiality of the data were collected and analyzed.

Consent for publication
Not applicable.
Availability of data and materials The data set are available from the corresponding author on reasonable request.

Competing interests
The authors declare that they have no competing interests.

Funding
The present study was Ph.D. thesis of the rst author and was funded by the Tehran University of Medical Sciences.

Authors' contributions
All the authors contributed to the conception and design of the study. ZR collected and analyzed the data and wrote rst version of the manuscript. ZK and RM supervised the study and participated in all part of study including designing the study, data analysis and manuscript writing. SN contributed in data analysis of quantitative phase and evaluated the manuscript. All authors approved the nal version.