Scholarly article on topic 'Validation study of the Fertility Problem Inventory in Iranian infertile patients'

Validation study of the Fertility Problem Inventory in Iranian infertile patients Academic research paper on "Health sciences"

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{"Fertility Problem Inventory (FPI)" / Validity / Reliability / Infertility}

Abstract of research paper on Health sciences, author of scientific article — Reza Omani Samani, Amir Almasi-Hashiani, Fatemeh Shokri, Saman Maroufizadeh, Samira Vesali, et al.

Abstract Introduction: Developing a tool for measuring patient’s problems is a vital step in the process of infertility treatment and research. Fertility Problem Inventory (FPI) is a questionnaire, which was made by Newton in 1999 to detect fertility problem associated within fertile couples, including 46 questions and five domains. Since validity and reliability of any instrument should be evaluated in the new environment and culture, the aim of this study was to assess the validity and reliability of the FPI in Iranian infertile couples. Materials and methods: Four hundred and ten patients in different stages of infertility treatment filled Fertility Problem Inventory. Forty-five patients answered the questionnaire twice at an interval of 2weeks. Reliability and validity of the questionnaire were measured by Cronbach’s alpha, interclass correlation, test retest, inter-rater agreement (IRA), exploratory factorial analyses and multi-trait scaling analysis. Results: Using a conservative approach, the IRA for the overall relevancy and clarity of the tool was 88.34% and 92.14%, respectively. Overall appropriateness and clarity were 92.23% and 94.48%, respectively. Overall integrity of the instrument was determined to be 87%. Cronbach’s alpha coefficient was greater than 70% for all domains. The ICC ranged between 0.78 (Relationship concern) and 0.92 (Sexual concern). Exploratory factorial analyses demonstrate five fields suitable for instrument. The correlation of each item with its own scale (Rho⩾0.4) represented a high convergent validity. In the discriminant validity of the tool, the correlation of each item with its own hypothesized domain was also greater than its correlation with other areas of the questionnaire. Conclusion: The results showed that Persian version of the FPI is a reliable and valid instrument for measuring the fertility problems in infertile patients.

Academic research paper on topic "Validation study of the Fertility Problem Inventory in Iranian infertile patients"

Middle East Fertility Society Journal (2016) xxx, xxx-xxx

Middle East Fertility Society Middle East Fertility Society Journal

www.mefsjournal.org www.sciencedirect.com

ORIGINAL ARTICLE

Validation study of the Fertility Problem Inventory in Iranian infertile patients

Reza Omani Samani, Amir Almasi-Hashiani, Fatemeh Shokri, Saman Maroufizadeh, Samira Vesali, Mahdi Sepidarkish *

Department of Epidemiology and Reproductive Health, Reproductive Epidemiology Research Center, Royan Institute for Reproductive Biomedicine, ACECR, Tehran, Iran

Received 19 June 2016; accepted 7 July 2016

KEYWORDS

Fertility Problem Inventory

(FPI);

Validity;

Reliability;

Infertility

Abstract Introduction: Developing a tool for measuring patient's problems is a vital step in the process of infertility treatment and research. Fertility Problem Inventory (FPI) is a questionnaire, which was made by Newton in 1999 to detect fertility problem associated within fertile couples, including 46 questions and five domains. Since validity and reliability of any instrument should be evaluated in the new environment and culture, the aim of this study was to assess the validity and reliability of the FPI in Iranian infertile couples. Materials and methods: Four hundred and ten patients in different stages of infertility treatment filled Fertility Problem Inventory. Forty-five patients answered the questionnaire twice at an interval of 2 weeks. Reliability and validity of the questionnaire were measured by Cronbach's alpha, interclass correlation, test retest, interrater agreement (IRA), exploratory factorial analyses and multi-trait scaling analysis. Results: Using a conservative approach, the IRA for the overall relevancy and clarity of the tool was 88.34% and 92.14%, respectively. Overall appropriateness and clarity were 92.23% and 94.48%, respectively. Overall integrity of the instrument was determined to be 87%. Cronbach's alpha coefficient was greater than 70% for all domains. The ICC ranged between 0.78 (Relationship concern) and 0.92 (Sexual concern). Exploratory factorial analyses demonstrate five fields suitable for instrument. The correlation of each item with its own scale (Rho P 0.4) represented a high convergent validity. In the discriminant validity of the tool, the correlation of each item with its own hypothesized domain was also greater than its correlation with other areas of the questionnaire. Conclusion: The results showed that Persian version of the FPI is a reliable and valid instrument for measuring the fertility problems in infertile patients.

© 2016 Middle East Fertility Society. Production and hosting by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

Corresponding author at: Department of Epidemiology and Reproductive Health, Reproductive Epidemiology Research Center, Royan Institute for Reproductive Biomedicine, ACECR, P.O. Box: 16635148, Tehran, Iran. Fax: +98 2123562678. E-mail addresses: r.samani@gmail.com (R.O. Samani), mahdi.sepidarkish@gmail.com (M. Sepidarkish). Peer review under responsibility of Middle East Fertility Society.

http://dx.doi.org/10.1016/j.mefs.2016.07.002

1110-5690 © 2016 Middle East Fertility Society. Production and hosting by Elsevier B.V.

This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

1. Introduction

In the past two decades, infertility has increased about 50%, so that of every 6 couples in reproductive age, one couple suffers from infertility (1). It has been identified as critical in the life, and threats the stability of individual and social relations (2). The World Health Organization (WHO) proposed infertility as a health problem around the world. In a study at the International Institute of Health in Belgium, France, and the Netherlands, it is shown that infertility is considered the fourth rank from the list of 12 critical events after the death of the mother, father, and spouse in fidelity according to the intensity of the tension among stressful life experiences by infertile women (3).

More than one and a half million couples face infertility problems in Iran (4). According to the screening in 2005, about a quarter couples experience primary infertility (5). Infertility is not just a medical issue, but often infertile couples are faced with crisis in all aspects of life (6). Couples who have been in this crisis situation are more than others at risk for depression, anxiety, low self-esteem, and dissatisfaction (7). The problem of infertility is more deeply in Iranian culture, in which there are large families. Since parents and relatives play an important role in the lives of couples, a delay in pregnancy makes a concern in couples because of curiosities and pressures by their family and others (8). This kind of attitude is not only related to Iranian community, but also is seen in other communities, and there are similar reactions to infertility in different communities (9). Infertile people are more susceptible to high extreme depression and anxiety. Lack of attention to emotional disorders in infertile couples and secondary symptoms of infertility develop a vicious cycle reducing the successful treatment (10). In addition to the physical and psychological problems of infertility, deficiency of standardized tools to measure fertility problem leads to a lack of awareness and undermining the problem (11,12).

The overall tools for fertility problems assessment generally measure the structure of fertility problems, and have no sensitivity required for precise measurement of fertility problems in infertile people. Other dedicated tools, such as infertility self-efficacy scale, infertility reaction scale, and coping scale for infertile couples, include fewer areas, and have no ability to assess all areas of fertility problems (13-15).

The Fertility Problem Inventory (FPI), built by Newton in 1999, is a multi-dimensional tool, and able to measure the stress and problems of infertility. Validity and reliability of the questionnaire were approved in different countries (16). However, it is necessary to confirm validity and reliability of every tool before the use of any tool in a society and culture. The aim of this study was to standardize and evaluate the validity and reliability of FPI in Iranian infertile patients.

2. Methods

The study population was infertile patients, referred to Royan Institute, a referral infertility treatment center in Tehran, the capital of Iran. Simple random sampling was done based on the medical records of patients in this center. After necessary coordination with the authorities of the center and taking permission, the number of sample size required was selected using

a table of random numbers. At first contacts with patients were established, and then the purpose of the study was explained. Fulfilling the questionnaire was patient's informed consent.

2.1. Translation, validity, and reliability

The original English version of FPI was translated into Persian by two independent expert translators independently. The translated version was reviewed by translators and one of the researchers, and compared with the original English version. After discussing the existing differences, final agreement on the translation was carried out, and ultimately a final translation was developed. The other two professional translators translated the Persian version to English, while they were independent and unaware of the content of the original version. All translations were reviewed, and the Persian version was developed by a selected team of specialists (17).

2.2. Face and content validity

To assess face and content validity of FPI, the questionnaire was sent to 10 experts in psychology, sexology, and methodology via e-mail. The validity index for each question, and total validity were calculated. To equalize the experts' conception of content validity indices (relevancy, clarity, and comprehensiveness of the tool), the definitions of these indices were sent with the questionnaire. Relevancy, clarity, and comprehensiveness were defined as follows, respectively. Ability of selected questions to reflect the content was as relevancy, questions' lucidity concerning their wording and concept was clarity; the instrument ability to include all content domains or areas was comprehensiveness. The experts were asked to review clarity and relevancy of every item, and comprehensiveness of the total questionnaire to give scores from 1 to 4 (1 = inappropriate, 2 = somewhat appropriate, 3 = appropriate, 4 = quite appropriate). Experts' responses were obtained within 1-3 weeks (18,19).

The inter-rater agreement (IRA) is the degree of observed agreement among the experts who participated in the study about the relevancy and clarity of the questions by a conservative approach (20). To measure IRA for relevancy as well as clarity of the instrument, the number of the questions which all (100%) of the experts selected "quite appropriate" and "appropriate", or "somewhat appropriate and "inappropriate" for relevancy and clarity (that is, the number of questions that all experts agreed on the rate of their appropriateness for relevancy and clarity) was divided by the total number of items. The acceptable level (cutoff point) of this index was considered 80% in this study. To calculate the clarity as well as relevancy of each question, the total number of experts who selected "appropriate" or "quite appropriate" for the clarity and relevancy of each item was divided by the total number of the experts (21).

To measure the relevancy of the total tool, the total number of the questions with appropriate relevancy was divided by the total number of questions. Total clarity of the tool was calculated in the same way. The level of 80% was considered acceptable. The comprehensiveness of tool was achieved by dividing the number of experts who detected the comprehensiveness of the tool as appropriate by the total number of experts.

Table 1 Demographic and fertility characteristics of the participants.

Age (years)a 31.28 (5.42)

Duration of infertility (years)a 4.93 (4.01)

Duration of marriage (years)a 7.07 (4.23)

Number of previous abortiona 1.04 (0.87)

Sexb Male 168 (41.5)

Female 237 (58.5)

Cause of infertilityb Male factor 146 (36)

Female factor 88 (21.7)

Both 71 (17.5)

Unexplained 100 (24.8)

Type of infertilityb Primary 287 (70.9)

Secondary 118 (29.1)

Educational levelb Primary 90 (22.2)

Secondary 150 (37)

University 165 (40.8)

Previous treatment failureb 0 208 (51.35)

1 81 (20)

2 61 (15.06)

3 36 (8.88)

P4 19 (4.69)

History of abortionb No 316 (78)

Yes 89 (22)

a Values given as mean SD (standard deviation). b Number (percentage) unless otherwise indicated.

2.3. Construct validity

The purpose of the assessment of construct validity is the answer to this question is that the structure of the questionnaire is consistent to some extent with the primary objective of making the questionnaire (measuring fertility problems in infertile). To measure construct validity, the Exploratory Factor Analysis (EFA) was used. In this technique, the correlation pattern between variables was measured, and then grouped using statistical methods (22). To assess construct validity of FPI, the principal component analysis with Promax rotation was used for factor structure of the questionnaire. To determine the assumptions of EFA and adequacy of sampling, the tests used were sphericity and the Kaiser-Meyer-Olkin measure of sampling adequacy, respectively. The factors that have eigenvalue over one were selected as factors of questionnaire. In order to ensure the accuracy of the number of scale factors, the number of factors obtained in this way was compared with factors obtained from the Scree plot (22).

2.4. Multi-trait scaling analysis

The convergent validity of each item is a strong item-own-scale correlation. The authors recommend a correlation coefficient for convergent validity of the questionnaire should be greater than 0.4. For item discriminant validity, there is a weak correlation between the questions related to a domain with other domains. In the other words, the correlation coefficient between a question and other domains should be less than the correlation coefficient between the question and its related domain.

2.5. Reliability (internal consistency)

To measure internal consistency, Cronbach's alpha coefficient which measures the degree of uniformity questions was used. Cronbach's alpha greater than 7.0 was satisfactory (23).

2.6. Reliability (intra class correlation)

Intra-class correlation coefficient (12) was used to evaluate test-retest reliability. ICC was calculated in two steps of pretest and posttest using comparing the total score of the questionnaire and its domains. ICC greater than 7.0 was satisfactory (24).

2.7. The tool of study

FPI is a questionnaire, which was made by Newton in 1999 to detect stress associated with infertility, including 46 questions and five domains (social concern, sexual concern, relationship concern, rejection of parenthood, and need for parenthood). It is a 6-point Likert scale, from strongly disagree = 1 to strongly agree = 6. In the tool, 19 questions score inversely. The scores are between 46 and 276. The higher numerical values represent higher levels of stress (16).

3. Results

3.1. Clinical and demographic characteristics of patients

Between February 2014 and April 2015, 410 participants completed the questionnaires. Five questionnaires (1.21%) were excluded due to the completion rate of less than 70%. The mean age was 31.28± (5.42). Clinical and demographic characteristics of the participants are shown in Table 1.

Table 2 Selected factors to FPI.

Total variance explained

Component Initial eigenvalues Extraction sums of squared loadings

Total % Of variance Initial eigenvalues Total % Of variance Cumulative %

1 14.7 45.94 45.94 8.89 27.8 27.8

2 4.4 13.76 59.7 6.4 19.99 47.8

3 3.11 9.72 69.42 5.94 18.57 66.37

4 2.44 7.63 77.06 2.79 8.73 75.1

5 1.73 5.41 82.47 2.35 7.37 82.47

3.2. Content validity

IRAs obtained from relevancy and clarity were 88.34% and 92.14%, respectively, according to conservative approach and experts' comments. The total relevancy and clarity were 92.23% and 94.48%, respectively. The total comprehensiveness was 87%.

3.3. Construct validity

After ensuring about the meaningfulness of Bartlett test of sphericity (p value < 0.001) and the sampling adequacy by

using Kaiser-Meyer-Olkin measure of sampling adequacy, five factors with eigenvalue of more than 1 were selected. A total of 82.47% of the variance was justified by the 5 factors. Table 2 shows the factors selected for FPI.

3.4. Multi-trait scaling analysis

The correlation of each item with its own scale and also with other areas was measured using multi-trait scaling analysis. The correlation of each item with its own scale (Rho p 0.4) represented a high convergent validity. In the discriminant validity of the tool, the correlation of each item with its own

Table 3 Multi-trait scaling analysis: the correlation of each item with its own domain and other domains.

The number of Domain 1 social Domain 2 sexual Domain 3 relationship Domain 4 rejection of Domain 5 need for questions concern concern concern parenthood parenthood

4 0.873 0.614 0.257 0.32 0.202

6 0.737 0.629 0.143 0.452 0.278

8 0.771 0.503 0.539 0.228 0.382

13 0.935 0.387 0.512 0.197 0.602

15 0.709 0.362 0.407 0.55 0.512

23 0.94 0.311 0.422 0.532 0.533

29 0.814 0.452 0.384 0.217 0.423

38 0.943 0.502 0.169 0.243 0.139

43 0.673 0.662 0.250 0.227 0.651

45 0.763 0.15 0.214 0.612 0.432

2 0.361 0.809 0.136 0.485 0.234

7 0.231 0.908 0.112 0.401 0.342

14 0.571 0.746 0.104 0.012 0.501

21 0.598 0.741 0.015 0.435 0.122

25 0.16 0.529 0.118 0.424 0.135

27 0.288 0.676 0.245 0.407 0.198

32 0.174 0.864 0.278 0.322 0.165

39 0.043 0.775 0.252 0484 0.233

3 0.457 0.653 0.938 0.369 0.342

18 0.304 0.546 0.942 0.650 0.257

22 0.65 0.486 0.833 0.514 0.146

26 0.529 0.380 0.883 0.636 0.532

28 0.497 0.512 0.695 0.342 0.518

34 0.252 0.339 0.816 0.164 0.406

36 0.507 0.275 0.776 0.252 0.424

37 0.333 0.008 0.788 0.407 0.387

41 0.335 0.493 0.801 0.133 0.462

42 0.401 0.238 0.944 0.235 0.511

5 0.382 0.367 0.203 0.867 0.452

9 0.11 0.214 0.228 0.823 0.302

10 0.424 0.361 0.319 0.795 0.462

16 0.169 0.244 0.012 0.856 0.424

17 0.613 0.13 0.109 0.976 0.169

20 0.076 0.112 0.503 0.788 0.613

33 0.369 0.432 0.026 0.925 0.176

46 0.250 0.436 0.416 0.751 0.039

1 0.214 0.296 0.386 0.380 0.808

11 0.136 0.540 0.2 0.512 0.686

12 0.112 0.217 0.109 0.339 0.749

19 0.104 0.319 0.291 0.275 0.829

24 0.212 0.354 0.099 0.008 0.896

30 0.325 0.414 0.233 0.432 0.814

31 0.339 0.237 0.029 0.436 0.675

35 0.387 0.228 0.163 0.015 0.879

40 0.291 0.234 0.158 0.118 0.636

44 0.288 0.509 0.179 0.245 0.834

Numbers in bold font: item own scale correlation higher than item correlation with the other scales of the area.

Table 4 FPI subscales, mean, standard deviation, internal consistency reliability, and intra-class correlations.

FPI subscale Number of items Descriptive statistics Reliability analysis

Mean SD Cronbach's alpha ICC % Floor % Ceiling

Social concern 10 34.36 5.46 0.91 0.85 20.1 24.8

Sexual concern 8 28.96 4.17 0.79 0.92 8 9.4

Relationship concern 10 36.9 3.58 0.86 0.78 13 18.9

Rejection of parenthood 8 24.73 5.01 0.95 0.9 14 16.4

Need for parenthood 10 37.37 5.09 0.83 0.8 26.7 11.7

Total scale 46 162.33 9.96 86.78 0.85 8 3

hypothesized domain was also greater than its correlation with other areas of the questionnaire. Table 3 shows the correlation of each item with its own domain and other domains.

3.5. Internal consistency

Cronbach's alpha coefficient was greater 70% for all domains and the total tool Cronbach's alpha coefficient for the total domains and the questionnaire is shown in Table 4.

3.6. Intra class correlation

The reliability of the questionnaire and all the questions was significantly lower than 0.001. The ICC ranged between 0.78 (Relationship concern) and 0.92 (Sexual concern). ICC of the total scales and items of the questionnaire is shown in Table 4.

4. Discussion

Our findings showed that the Persian version of FPI is a valid and reliable tool to measure problems in infertile patients. Content validity measurement of the tool indicated that the translation process from English into Persian is correct and logical considering translation into Persian, equalizing words, reverse translation, revision of the translation, review, and being understandable and acceptable (17). It also could be argued that the Persian version is consistent not only with the English version, but for the target group is also clear and expressive. To validate the content of a tool, as is common, a panel of experts was used in most studies (21). To measure content validity, quantitative indicators were used. Finally, after the calculation, one or several numbers are reported as the index. One of the accepted methods in the field is calculating the CVI index. According to the various methods related to CVI by Polit et al. in 2007, it is easily understandable than other forms of calculation of the content validity. In that study, CVI was greater than 0.75 or 0.8 is acceptable according to 3-10 experts' comments (25). The results of this study showed that this questionnaire has been approved by the majority of experts according to the mean score of 87% of comprehensiveness. The lowest mean score was related to relevancy of the questions (0.83), which suggested that all questions were well-designed with the high content validity.

In our study, the load factor of the questions was high. The acceptance cutoff point of 0.4 for load factors revealed that all 46 questions in the questionnaire had the acceptable load factor. These findings suggested that all questions of the tool were important, and had appropriate validity based on EFA. Therefore, the construct validity of the questionnaire was appropri-

ate. Based on EFA, 5 main factors were well correlated with its original form, and explained a total of 82.47% of the total variance.

Psychometric experts consider the correlation between the subscales of a test together as internal consistency and construct validity of the test. In our study, the correlation coefficients showed that dimensions or subtests are more or less orthogonal to each other. Weak correlation between questions in an area with other areas suggested that the questions are linked, but each takes into account different components of fertility problems, and various areas are able to measure the desired objectives.

According to our results, Cronbach's alpha coefficients obtained from the 46-item questionnaire are acceptable for fertility problems in all areas. It represents the internal consistency of this tool. The results of the test-retest also were satisfactory for the scale within a month, indicate the stability of results over time and consistent with the results of studies in other parts of the world. Newton also reported the reliability of the questionnaire using the Cronbach's alpha equal to 0.93 (16). The reliability coefficients obtained from the original and Persian versions of the tool were satisfactory. Therefore, the tool is reliable. In our study, the distribution of responses was assessed using the floor and ceiling effect. Areas such as asexual concerns and social concerns had high proportions of floor scores (over 20%). This may be due to low mean age of the patients and low average years of infertility. The unwillingness of patients to discuss sexual concerns could also be one reason for the high floor score in the area.

Accuracy is required for any research. However, limitations for methodological issues and generalizability of the results should not be ignored. One of the limitations of the study was sampling from an infertility treatment center. Although this is a referral center, the results need to interpret more cautiously. Repetition of the research on multicenter samples with larger sample size can facilitate generalizability of the results. The strengths of this study were to review the validity and reliability of indicators, and appropriate sample size and the large number of patients (n = 45) for calculating the ICC.

According to the study by Newton et al. in 1999, the number and content of questions were appropriate, so that the tool maintained its structure with minimum changes and without removing the existing questions (16). The racial and cultural differences and different experiences that Iranian learners experience cannot lead to different outcome expectancies compared with English-language learners. The complexity of questions was little, and a few of the questions were unanswered. It indicates the higher level of acceptance for the questions by the patients.

5. Conclusion

According to psychometric properties, the extensive use of this tool provides researchers appropriate validity and reliability of the questionnaire, comprehensiveness, and easy to understand. The tool in Iranian society has satisfactory reliability and validity. It can be used in therapeutic and research situations.

Conflict of interest

The authors declared no conflict of interest. References

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