Scholarly article on topic 'Validation of a Korean Version of Fertility Problem Inventory'

Validation of a Korean Version of Fertility Problem Inventory Academic research paper on "Psychology"

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{infertility / "reliability and validity" / stress}

Abstract of research paper on Psychology, author of scientific article — Ju Hee Kim, Hye Sook Shin

Summary Purpose The Fertility Problem Inventory (FPI) is a screening instrument used to identify infertility-related stress. The purpose of this study was to assess the reliability and validity of the Korean version of the FPI. Methods Forward–backward translation of the FPI from English to Korean was conducted. The translated instrument was pilot-tested and administered to 259 women with infertility. Test-retest reliability was conducted and the internal consistency coefficient was determined. Validity was evaluated through content validity, construct validity with confirmatory factor analysis, discriminant validity, and convergent validity. Results The internal consistency was satisfactory (Cronbach's alpha = .92, item-total correlations = .60–.92). The overall content validity index was 96.9%, signifying that the FPI had good content validity. The model fit indexes were acceptable (goodness of fit index = .92, adjusted goodness of fit index = .91, normal fit index = .95, comparative fit index = .93, and root mean square error of approximation = .05), indicating good construct validity. The intercorrelations were significant, although low to moderate in size (.20–.59). The correlation between the FPI and depression ranged from .32 to .51 (p < .001), while the correlation between the FPI and the fertility-related quality of life ranged from –.35 to –.58 (p < .001). Conclusion The Korean version of the FPI has high reliability, and good content, construct, discriminant, and convergent validity. A validated Korean version of the FPI may help nurses identify infertility-related stress and administer appropriate nursing interventions to Korean women with infertility.

Academic research paper on topic "Validation of a Korean Version of Fertility Problem Inventory"

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Asian Nursing Research

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Research Article

Validation of a Korean Version of Fertility Problem Inventory

Ju Hee Kim, RN, PhD, Hye Sook Shin, RN, PhD *

College of Nursing Science, Kyung Hee University, Seoul, South Korea

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ARTICLE INFO

Article history:

Received 27 September 2013 Received in revised form 29 December 2013 Accepted 24 March 2014

Key words: infertility

reliability and validity

stress

SUMMARY

Purpose: The Fertility Problem Inventory (FPI) is a screening instrument used to identify infertility-related stress. The purpose of this study was to assess the reliability and validity of the Korean version of the FPI.

Methods: Forward—backward translation of the FPI from English to Korean was conducted. The translated instrument was pilot-tested and administered to 259 women with infertility. Test-retest reliability was conducted and the internal consistency coefficient was determined. Validity was evaluated through content validity, construct validity with confirmatory factor analysis, discriminant validity, and convergent validity.

Results: The internal consistency was satisfactory (Cronbach's alpha = .92, item-total correlations = .60—.92). The overall content validity index was 96.9%, signifying that the FPI had good content validity. The model fit indexes were acceptable (goodness of fit index = .92, adjusted goodness of fit index = .91, normal fit index = .95, comparative fit index = .93, and root mean square error of approximation = .05), indicating good construct validity. The intercorrelations were significant, although low to moderate in size (.20—.59). The correlation between the FPI and depression ranged from .32 to .51 (p < .001), while the correlation between the FPI and the fertility-related quality of life ranged from —.35 to —.58 (p < .001).

Conclusion: The Korean version of the FPI has high reliability, and good content, construct, discriminant, and convergent validity. A validated Korean version of the FPI may help nurses identify infertility-related stress and administer appropriate nursing interventions to Korean women with infertility.

Copyright © 2014, Korean Society of Nursing Science. Published by Elsevier. All rights reserved.

Introduction

Infertility refers to failure to conceive, even if individuals have had unprotected intercourse for a year or more (Zegers-Hochschild et al., 2009). Infertility affects approximately 9—15% of couples worldwide (Boivin, Bunting, Collins, & Nygren, 2007).

Research on infertility shows that women with infertility experience not only individual psychological distress, such as feelings of inadequacy, depression, grief, guilt and stigma (Onat & Beji, 2012; Park, 1995; Slade, O'Neill, Simpson, & Lashen, 2007), but also marital distress such as an impaired sexual life, marital dissatisfaction and poor marital communication (Gourounti, Anagonostopoulos, & Vaslamatzis, 2011; Onat & Beji; Valsangkar, Bodhare, Bele, & Sai, 2011). In addition, women with infertility may feel isolated and neglected in an environment that highly values parenthood, and thus, may withdraw from their family and

* Correspondence to: Hye Sook Shin, RN, PhD, College of Nursing Science, Kyung Hee University, 26, Kyunghee-daero, Dongdaemun-gu, Seoul, 130-701, South Korea. E-mail address: suksh@khu.ac.kr

friends (Moura-Ramos, Gameiro, Canavarro, & Soares, 2012; Wilson and Kopitzke, 2002). Their social relationships may also be negatively affected because of the social pressure to achieve parenthood and distress due to other couples' pregnancies and childbirths (Cousineau & Domar, 2007; Moura-Ramos et al., 2012). This distress can affect the rate of pregnancy, success rate of infertility treatment, and drop-out rate. Matthiesen, Frederiksen, and Ingerslev (2011) found that infertility-related stress, state anxiety, and trait anxiety may reduce the rate of pregnancy when they conducted research on the relationship between infertility distress and the outcome of assisted reproductive technology through meta-analysis. Olivius, Friden, Borg, and Bergh (2004) have reported that 30% of couples with infertility ended treatment prematurely because of the psychological burden. Thus, infertility can give rise to psychological distress in varying forms among individuals, in their marital and social lives, and may affect subsequent pregnancy and the success of infertility treatment. Therefore, strategies and interventions aimed at reducing infertility-related stress are needed. In addition, a valid and reliable tool to measure infertility-related stress is essential.

http://dx.doi.org/10.1016/j.anr.2014.03.004

1976-1317/Copyright © 2014, Korean Society of Nursing Science. Published by Elsevier. All rights reserved.

Researchers have developed various instruments that measure infertility stress. Bernstein, Potts, and Matlox (1985) developed the Infertility Questionnaire, which measures psychological dysfunction in the areas of self-esteem, blame/guilt, and sexuality. The Fertility Problem Stress Inventory, developed by Abbey, Andrews, and Halman (1991), assesses different life domains that are disrupted by fertility problems. The Infertility Distress Scale assesses self-reported fertility-related stress among males with infertility (Pook, Rohrle, & Krause, 1999). In addition, many other tools measure fertility adjustment (Glover, Hunter, Richards, Katz, & Abel, 1999) and concerns regarding fertility treatment (KlonoffCohen & Natarajan, 2007). In South Korea, Kim, Park, and Jang (1995) developed the Infertility Stress Scale that comprises value feeling, obsession, sexual satisfaction, meanings of parenthood, marital satisfaction, family adaptation, and social adjustment. However, most measures are made up of one or two dimensions, or have been developed for general populations, but not individuals affected by infertility. For example, fertility-related stress is often assessed through general measures of anxiety and depression. Moreover, the validity of some measures has yet to be confirmed. Therefore, such measures may not be sensitive or specific enough to reflect the unique characteristics of women with infertility, which have multidimensional aspects (Boivin et al., 2007; Gourounti et al., 2011; Moura-Ramos et al., 2012; Newton, Sher-rard, & Glavac, 1999).

The Fertility Problem Inventory (FPI), developed by Newton et al. (1999), is an instrument that measures infertility-related stress. This is a multidimensional measure that identifies infertility-related stress in five different domains, namely, social concern, sexual concern, relationship concern, the need for parenthood, and rejection of a child-free lifestyle. The FPI has subsequently been translated into diverse languages and has been shown to be valid in many studies (Gourounti et al., 2011; Moura-Ramos et al., 2012; Peterson, Newton, & Rosen, 2003; Slade et al., 2007, van der Broeck, D'Hooge, Enzlin, & Demyttenaere, 2010). Despite its wide use in research, no published studies have confirmed the reliability and validity of the Korean version of the FPI.

We conducted this study in order to translate the FPI, and subsequently confirm the reliability and validity of the Korean version. A validated FPI, as intended by this study, may help health professionals, including nurses, to identify high stress and adjustment difficulties among women with infertility. In turn, this would enable health professionals to give the required individualized support and therapeutic interventions to affected women (Verhaak et al., 2007). The results from this study will be used as baseline data for understanding women with infertility and couples with such problems.

Methods

Study design

This was a methodological study aimed at assessing the reliability and validity of the Korean version of the FPI developed by Newton et al. (1999).

Setting and samples

This study was conducted between May and August 2013 in one of the largest infertility hospitals in Seoul, Korea, which performs approximately 400 artificial reproduction procedures per month. Women with infertility who visited the infertility clinic for medical treatment formed part of the study sample. Inclusion criteria were as follows: (a) women who had been diagnosed with infertility by

an obstetrician or medical doctor, (b) women with primary or secondary infertility without parity history, and (c) women who had previously undergone one or more infertility treatment.

The effect size was estimated by G*power 3.0. For an effect size of .30 and an alpha of .05 (two-tailed) with a power of .9, a minimum of 112 participants were required for a correlation analysis. In addition, confirmatory factor analysis (CFA), aimed at determining construct validity, required a minimum of 230 participants who were five times the number of questionnaire items. Ultimately, 265 women with infertility were recruited in anticipation of possible attrition. Data were subsequently collected from 259 participants; 6 participants were excluded from the study because of incomplete responses on the questionnaires.

Ethical consideration

The Research and Ethics Committee of Kyung Hee University approved this study protocol (KHSIRB-13-009). All the respondents were informed of the objectives of the study and consented to participation. They were also assured that the data that they provide would be treated as confidential and used in this study only, and that their decision to withdraw from the study would not compromise the standard of care that they receive at the clinic. All the participants signed the informed consent documents prior to the initiation of this project.

Measurements

General characteristics included age, educational level, employment status, religion, and socioeconomic status. Characteristics that are related to fertility included marital period, infertility treatment period, financial burden of the infertility treatment, and the cause of the infertility.

The FPI (Newton et al., 1999) is a 46-item, self-administered, multidimensional measure that identifies infertility-related problems in five homogeneous domains, namely, social concern, sexual concern, relationship concern, the need for parenthood, and the rejection of a childfree lifestyle. A composite score derived by summing all five domain scores is interpreted as providing a global measure of perceived infertility-related stress. The FPI requires respondents to indicate their degree of agreement with each item on a 6-point Likert scale ranging from strongly disagree (1) to strongly agree (6). The overall score ranges from 46 to 276, where the higher the score, the higher the fertility-related stress.

Depression was measured using the Beck Depression Inventory (BDI), developed by Beck (1967), and translated into Korean by Lee and Song (1991). The BDI is a 21-item, self-reported measure, that measures items on a 4-point Likert scale, where the higher the score, the higher the level of depression.

The fertility-related quality of life (FertiQoL) measure, developed by the European Society of Human Reproduction and Embryology and the American Society of Reproductive Medicine, has been translated into several languages, including Korean. The measure consists of 34 items that could collectively indicate the impact of fertility problems on quality of life. In addition, a core section relating to personal and interpersonal quality of life ("Core FertiQoL") and an optional section relating to treatment ("Treatment FertiQoL") form part of the measure. The Core FertiQoL is a 24-item, self-reported measure consisting of four domains: emotional (6 items), mind-body (6 items), relational (6 items), and social (6 items). The Treatment FertiQoL assesses quality of life during treatment, including any medical intervention or consultation according to the treatment environment (6 items) and treatment tolerability (4 items). The FertiQoL comprises items on a 5-point Likert scale, where the higher the score, the lower the

fertility-related quality of life (Boivin, Takefman, & Braveman, 2011).

Data collection

Translation and content validity

Permission to translate the FPI into Korean was obtained from the original author, Newton. The FPI was translated using the backtranslation technique (Maneesriwongul & Dixon, 2004). It was first translated from English into Korean by two bilingual medical and nursing professionals separately. Another expert and researcher reviewed the Korean translations together with the original English form for inconsistencies and meaning, taking context and culture into account. Subsequently, the questionnaire was translated back from Korean to English by a bilingual language expert. The back-translated and original forms of the FPI were then compared and found.

The content validity of the FPI was determined by measuring relevance, clarity, and comprehensiveness. The content validity of this tool was assessed by an expert panel comprising five academicians (3 professors specializing in maternity nursing and 2 professors specializing in reproductive medicine) using a content validity index (CVI). The experts were asked to rate each item based on its relevance (responses ranged from 1 to 4, with a score of 4 demonstrating high relevance), clarity (responses ranged from 1 to 4, with a score of 4 indicating high levels of clarity), and comprehensiveness (responses ranged from 1 to 4, with a score of 4 showing high levels of comprehensiveness) on a 4-point scale. Content validity was determined by an expert panel, who calculated content validity by considering the ratio of three or four points of all items; if the ratio was more than 0.8, then it was interpreted as indicative of a high content validity (Polit & Hunglar, 1999).

Pilot study

The translated version was administered to women with infertility in order to identify and resolve any potential problems regarding the translation. The pilot respondents comprised 20 women with infertility who met the inclusion criteria. This procedure enabled the modification of uncertain meaning and the confirmation of the estimated time for completing the questionnaire and the Korean version of the FPI.

Data collection

Women with infertility were invited to participate voluntarily in our study through a hospital announcement. Those who agreed to participate were given a letter explaining the purpose of the study, providing the researcher's affiliation and contact information, and clearly stating that responses would be confidential and anonymity would be guaranteed in the final data reports. Participants then completed the FPI questionnaire in a separate counseling room. The average completion time was 30 minutes; each participant received a book coupon as a reward for participating in the study.

Data analysis

Statistical analyses were carried out using SPSS Windows version 20.0 and AMOS 20.0 (SPSS, Chicago, IL, USA). Descriptive statistics were used to analyze respondent characteristics.

Test-retest reliability and the internal consistency coefficient were used to assess reliability. Internal consistency refers to the extent to which items within a scale are interrelated. A minimum Cronbach's alpha value of .70 is required for group comparisons (Polit & Hunglar, 1999). Test-retest reliability was assessed using

the intra-class correlation coefficient (ICC). We expected the ICC for the FPI items to exceed .7 (Polit & Hunglar).

Validity was evaluated through a combination of content validity, construct validity with CFA, discriminant validity, and convergent validity. CFA or exploratory factor analysis (EFA) was used to assess validity. While CFA aims to test whether a defined set of items fits the empirical data confirming a pre-existing theoretical model, EFA has no assumptions regarding the association between items and their underlying factors (Byrne, 2010). CFA, as opposed to EFA, is suitable for the application of an instrument to a new demographic group, when the validity of such an instrument has been theoretically proven (Woo, 2012). CFA has been used to measure construct validity while confirming factor loading between a latent variable and an observed set of variables, and for the evaluation of a model fit (Woo). The validity of the original version of the FPI was theory-based and had been confirmed (Gourounti et al., 2011; Moura-Ramos et al., 2012; Peterson et al., 2003; Slade et al., 2007, van der Broeck et al., 2010). Therefore, we conducted CFA to analyze the data of Korean women with infertility. The model verification was conducted on the basis of the chi-square test, goodness of fit index (GFI), adjusted goodness of fit index (AGFI), normal fit index (NFI), comparative fit index (CFI), and root-mean-square error of approximation (RMSEA).

Discriminant validity refers to the extent to which scales measure different constructs. In this study, discriminant validity was assessed by examining the intercorrelations between the five subscales, construct reliability and average variance extracted. Convergent validity refers to the extent to which a test correlates with other variables with which it should theoretically correlate. In this study, convergent validity was assessed by examining the in-tercorrelations between the FPI subscales and standardized measures of depression and the FertiQoL. Depression and FertiQoL were proven variables which were related to infertility distress in previous research (Boivin et al., 2011; Gourounti et al., 2011; Newton et al., 1999). Scales with a correlation > .7 are considered to overlap conceptually (Newton et al.).

Results

Participant characteristics

A total of 259 women with infertility completed the FPI questionnaire. Table 1 shows general and infertility-related characteristics of women with infertility. Half of the respondents (46.7%) were older than 35 years of age. In addition, 88% of the participants had a college degree or higher. The majority were employed (62.5%) and religious (57.9%), and 91.9% were categorized as middle class in terms of monthly income. Respondents who had been married for longer than 3 years accounted for 61.8% of respondents, and 85.7% had undergone infertility treatment for more than a year. Most of the women (90.0%) carried the financial burden of the infertility treatment, in spite of governmental subsidy. The main cause of infertility was unknown (38.2%), followed by the female factor (22.0%), the male factor (21.6%), and both (18.1%).

Reliability

Table 2 shows the reliability of the FPI subscales in terms of Cronbach's alpha coefficients. The FPI had a Cronbach's alpha of .92, indicting good internal consistency. Item total correlations varied from .60 to .87.

In order to assess the stability of the scale over time, the test-retest reliability of the scale was carried out after 2-3 weeks (further visits). Although we attempted to re-test all participants (n = 259), we were only able to re-test 210 respondents (83%)

Table 1 General and Infertility-related Characteristics of Respondents (N = 259)

Table 3 Fitness Indices for the Fertility Problem Inventory (FP!) Model

Variables N = Categories 259 n %

Age (yr) < 35 138 53.3

> 35 121 46.7

Educational level < University 31 12.0

> University 228 88.0

Employment status No 97 37.5

Yes 162 62.5

Religion No 109 42.2

Protestant 85 32.8

Catholic 28 10.8

Buddism 33 12.7

Others 4 1.5

Family monthly income (unit 10,000 KRW) < 200 21 8.1

200—500 170 65.6

> 500 68 26.3

Marital period (yr) <3 99 38.2

>3 160 61.8

Infertility treatment period (yr) <1 37 14.3

>1 222 85.7

Financial burden of infertlity treatment No 26 10.0

Moderate 42 16.3

Yes 191 73.7

Infertlity cause Unknwon 99 38.2

Female 57 22.0

Male 56 21.6

Both 47 18.1

Note. KRW = Korean Won.

because of successful pregnancies attrition. The ICC was .884 (p < .001) and the test-retest reliability of the FPI was considered adequate in the current study.

Validity

The content validity of the FPI was determined by measuring the relevance, clarity, and comprehensiveness of the measure. Relevance at both the item level and the instrument level yielded a mean score of 3.9 out of 4; clarity at the item level yielded a mean score of 3.8 out of 4; comprehensiveness at the item level yielded a mean score of 3.2 out of 4. The overall CVI was 96.9%, which signified that the FPI had good content validity.

Construct validity was determined through CFA, resulting in the chi-square value of 1013.36 (df = 478, p < .001). This demonstrated that the model fit indexes between the theoretical model and the data were acceptable (x2/df = 2.12, GFI = .92, AGFI = .91, NFI = .93, CFI = .90, and RMSEA = .05), as reported in Table 3.

The discriminant validity of the FPI subscales was assessed by examining the correlations between the five subscales, construct reliability and average variance extracted. Intercorrelations were significant, but low to moderate in size (from .20 to .59), and construct reliability and average variance extracted were .72

Table 2 Characteristics of Items in Fertility Problem Inventory

Subscale

N = 259

Cronbach's alpha

Social concern (10)

Sexual concern (8) Relationship

concern (10) Rejection of childfree

lifestyle (8) Need for

parenthood (10) Global stress (46)

9, 12, 14, 27, 30, 35, 39, 40, 43, 44 3, 4, 7, 13, 17, 22, 32, 37 11, 16, 18,21,24, 26, 33, 36, 45, 46

1, 15, 20, 25, 28,31, 38, 41

2, 5, 6, 8, 10, 19, 23, 29, 34, 42

all items

32.78 9.63

21.29 26.73

6.52 7.74

23.26 6.81

44.44 7.79

148.68 28.22

.79 .79

Index N = 259

C2/df GFI AGFI NFI CFI RMSEA

Criteria 2-3 > 0.9 > 0.9 > 0.9 > 0.9 < 0.1

FPI Model 2.12 .92 .91 .93 .90 .05

Note. GFI = goodness of fit index; AGFI = adjusted goodness of fit index; NFI = normal fit index; CFI = comparative fit index; RMSEA = root mean square error of approximation.

and .65 respectively. This showed that the FPI subscales were separate entities with discriminant validity (Table 4).

The convergent validity of the FPI subscales was assessed by testing correlations between the FPI, depression, and the FertiQoL. The correlation between the subscales of the FPI and depression ranged from .32 to .51 (p < .001), which was statistically significant. Results showed that depression was positively correlated with all the FPI subscales, suggesting that all the FPI subscales are assessing distress specifically related to fertility problems. The correlation between the FPI subscales and the FertiQoL ranged from —.35 to —.58 (p < .001), which was statistically significant. Results showed that the FertiQoL was negatively correlated with all the FPI sub-scales. These suggested that the FPI achieved convergent validity (Table 5).

Discussion

The purpose of this study was to evaluate the reliability and validity of the FPI when used on Korean women with infertility by determining internal consistency, test-retest reliability, CVI, construct validity by CFA, discriminant validity, and convergent validity. To the author's knowledge, this is the first study to assess the reliability and validity of the FPI in Korea. The FPI has been translated into many languages and used in many other studies. However, some studies (Gourounti et al., 2011; Moura-Ramos et al., 2012; Newton et al., 1999) determined the reliability and validity of the FPI through statistical analysis; the present study was modeled on such research.

This study used CFA to determine the construct validity of the FPI. This is because of the suitability of CFA in determining construct validity, coupled with the fact that this approach is less likely to influence the final factor structure owing to chance characteristics of the data (Fabrigar, Wegener, MacCallum, & Strahan, 1999). This study found that the Korean version of the FPI showed good reliability (Cronbach's alpha of .60—.92) and construct validity (GFI = .92, AGFI = .91, NFI = .95, CFI = .93, and RMSEA = .05) when used on Korean women with infertility. The original FPI study (Newton et al., 1999), consisted of 2,302

Table 4 Intercorrelation with Fertility Problem Inventory Subscales

Measures

N = 259

Social concern

Sexual concern

Relationship concern

Rejection Need for of childfree parenthood lifestyle

Social concern Sexual concern Relationship

concern Rejection of childfree lifestyle Need for parenthood

.51*' .48*'

*p < .05 ** p < .001.

Table 5 Correlation between Fertility Problem Inventory and Measures of Depression and Fertility Quality of Life (FertiQoL)

Measures N = 259

Depression FertiQol

Social concern .51** -.58**

Sexual concern .46** -.46**

Relationship concern .49** -.39**

Rejection of childfree lifestyle .32** -.35**

Need for parenthood .48** -.53**

Global stress .59** -.62**

*p < .05, ** p < .001.

participants, who were men and women with infertility problems in Canada. Newton et al. reported that the FPI is a reliable measure of perceived infertility-related stress and taps into specific information pertaining to five separate domains of patients' concerns by determining internal consistency (Cronbach's alpha of .77-.87), discriminant (correlation of .26-.66) and convergent validity (correlation of .29-.62), respectively. Gourounti et al. (2011) studied 108 Greek women with infertility in the first study to assess the factorial structure of the FPI using EFA. In that study, EFA showed that the FPI comprised four factors and that the majority of items relating to relationship and sexual concerns could be grouped into one solid factor, named "spousal concern". Very strong associations were noted between the original FPI scales and the derived scales, indicating that no information is lost when the items are rearranged. Their study confirmed that the FPI had a relatively stable factor structure and satisfactory reliability (Cronbach's alpha of .65-.84) as well as convergent (correlation of .25-.56) and discriminant validity (correlation of .18-.58). Furthermore, Moura-Ramos et al. (2012) studied 209 Portuguese women with infertility in the first study dedicated to testing the factor structure of the FPI using CFA. In that study, two higher-order models were tested. The first model tested the original framework proposed by Newton et al., with five first-order factors presumably correlated and loading on a second-order factor, named "infertility global stress". The second model included an intermediate level of two latent variables. The five first-order factors loaded reliably on the two second-order factors consisting of the latent variables, which reflect (a) the problematic infertility domains, and (b) representations about the importance of parenthood in the lives of affected men and women. These latent variables loaded significantly on the scale's overall score, namely, global infertility stress. The best fitted model was Model 2 (CFI = .95, RMSEA = .06, and SRMR = .06).

The results of the current study indicated that the Korean version of the FPI represented satisfactory discriminant validity (range of .20-.59). Previous studies support these results (Gourounti et al., 2011; Moura-Ramos et al., 2012; Newton et al., 1999). In studies by Newton et al. and Gourounti et al., in-tercorrelations between the FPI subscales were in the ranges of .26-.66 and .25-.56, suggesting that the FPI had good discriminant validity.

The convergent validity of the Korean version of the FPI proved to be satisfactory in this study. All correlations between depression and the FertiQoL were moderate. These results are compatible with those obtained in previous research (Gourounti et al., 2011; Newton et al., 1999). Newton et al. inspected intercorrelations between the FPI scales and standardized measures of depression, anxiety, and marital adjustment. These authors confirmed that the FPI was related to depression (correlations of .29-.53), anxiety (correlations of .16-.34), and marital adjustment (correlations of -.14 to -.52). In the study by Gourounti et al., measures of anxiety, depression, and mood states were used to assess the convergent validity of the FPI. These authors reported that the FPI correlated

with depression (ranges of .18-.58), anxiety (ranges of .20-.43), and marital adjustment (ranges of .13-.44). However, in this study, depression and the FertiQoL showed a higher correlation with "social concern" and the "need for parenthood" than the other three subscales of the FPI did. Previous studies reported that "sexual concern" is more correlated with depression than the other subscales of the FPI. While "sexual concern" means diminished sexual enjoyment or sexual self-esteem, or that one cannot easily engage in scheduled sexual relations, "social concern" refers to sensitivity to comments, reminders of infertility, feelings of social isolation, and alienation from family or peers. Presumably, the Eastern culture, including the Korean cultural context, puts considerable value on others' views, while Western culture highly values individual well-being. These cultural differences are reflected in these studies, although the study design does not enable any inferences regarding causal relations from the findings.

Some limitations should also be considered when analyzing the present data. First, the data were obtained from a relatively small sample of women with infertility, drawn from only one infertility hospital. Therefore, the results from this study cannot be conclusively applied to all Korean women with infertility. Nevertheless, the sampled hospital is one of the largest infertility hospitals in Korea, performing approximately 400 artificial reproduction procedures per month. In addition, the sample consists of various demographic and infertility-related characteristics of women with infertility. Consequently, this sample is considered to be representative of women with infertility in Korea. Secondly, participants in this study were limited to clinic-based samples of women seeking treatment for their infertility; therefore, the findings of this study cannot be generalized. Thus, future studies must include women with infertility who are not seeking treatment. Finally, the findings from this study have shown that most women with infertility (90.0%) carried a financial burden due to the costs associated with the treatment of their infertility, in spite of governmental subsidy. The potential importance of other domains, such as financial concerns (Smeenk, Verhaak, Stolwijk, Kremer, & Braat, 2004), stigma (Donkor & Sandall, 2007), and low self-esteem (Miles, Keitel, Jackson, Harris, & Licciardi, 2009) remains unexplored, and hence, must be explored in order to identify infertility-related stress.

Conclusion

It was confirmed that the Korean version of the FPI showed high reliability and good content, construct, discriminant, and convergent validity. A validated Korean version of the FPI may help nurses identify infertility-related stress and help them develop appropriate nursing interventions for Korean women with infertility.

Conflict of Interest

The authors have no conflicts of interest to declare.

Acknowledgments

We are grateful to the women who participated in this study without whom this study would not have been possible.

References

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