The PGIS was first developed in 1998 by Professor Hutti et al. [4] at the School of Nursing, University of Louisville, as a clinical assessment tool for perinatal grief intensity and then validated by them in 2018 with repeated applications to have high reliability and validity in identifying current grief intensity and predicting women at greatest risk for future intense grief, severe depression, anxiety, and also women who require follow-up after perinatal miscarriage [5, 6]. Therefore, the Hutti Perinatal Grief Intensity Theoretical Framework and the current PGIS were developed in 2019 to help nurses assess the intensity of grief and provide efficient, relationship-oriented care [7]. The PGIS has 14 items in three dimensions (reality, confront others, and congruence). The reality dimension is scored on a four-point Likert scale (4 = completely disagree, 3 = disagree, 2 = agree, and 1 = completely agree), and the confront others and congruence dimensions are scored reversely (1 = completely disagree, 2 = disagree, 3 = agree, and 4 = completely agree). The total PGIS score is calculated as 3.08 + 0.41 $\times$ reality dimension score – 0.2 $\times$ confront others dimension score – 0.15 $\times$ congruence dimension score. The higher the total score, the more severe the grief reaction of the pregnant woman to the loss of the fetus, and a total scale score of less than 3.535 was considered a normal grief reaction, with 3.535 as the best cut-off point to indicate severe grief. Cronbach’s alpha coefficient of the original scale was 0.82, Cronbach’s alpha coefficient of each dimension was 0.70–0.82, and the content validity index (CVI) was 0.924, with good reliability and validity [8]. The validity was supported by factor analysis, which accounted for 66.94% of the total variance, with a sensitivity of 61.3% and specificity of 84.4%.

(1) Authorization: Using the e-mail address of the professor who developed the English version of the PGIS scale, the research team requested the original version and the author’s permission to use the PGIS.

(2) Translation and cultural debugging: The Brislin translation model was used, and cross-cultural debugging guidelines were followed for scale translation, integration, back-translation, re-translation, cultural debugging, and pre-survey. Two clinical nursing experts and one psychology expert from the hospital were invited to conduct independent scale translation. A doctor from the hospital who was fluent in medical English was asked to discuss and revise it in collaboration with the subject group members to initially form the translated version A. Two bilingual translators (an English teacher and a psychology teacher from a university medical school) who had not been exposed to the English version of the scale were asked to independently back-translate the translated version to form the back-translated version B. The original scale, translated version A, and back-translated version B were sent to the mentioned experts to compare and discuss the original English scale and the back-translated version B in terms of the meaning of its words, concepts, and expressions, and revise and adjust the translated version A, and then translate it to form the version C. The scale was then evaluated and version D was developed.

(3) Pre-survey: Using the convenience sampling method, 30 subjects were selected for a pre-survey in August 2021 to evaluate the subjects’ understanding of the scale content and record relevant recommendations. The inclusion criteria for this study were as follows: individuals aged 18 years or older, gestational week of at least 10 weeks, a history of at least one perinatal loss, conception occurring naturally, and fetal abnormalities that necessitated termination of pregnancy. Participants with cognitive impairment or unconsciousness were excluded from the study. The subjects provided informed consent and willingly participated in the research upon hospitalization. They completed the reality dimension of the PGIS immediately after receiving the diagnosis and deciding to terminate their pregnancy. Furthermore, they were informed about a follow-up visit via telephone, scheduled for two weeks after the fetal abortion, during which they would complete the face-to-face dimension and the consistency dimension of the PGIS. Pre-survey feedback and suggestions from the expert group were combined to further adjust the language and content of version D, which finally formed the Chinese version of the scale (version E) for formal evaluation.

This study combined translation, cultural adaptation, expert opinion, and pre-survey results to revise the scales, and the specific comments are as follows: (1) The experts suggested that item 2 “I do not think this baby is a person” and item 3 “I don’t think this child has a specific personality yet” of the reality dimension be revised to “I do not think the baby during pregnancy has a specific personality” and “I don’t think that this baby has a specific personality” to avoid unnecessary cultural conflicts. (2) Sub-item 3 “In the first few hours and days after I lost a loved one, if people said or did something that made me feel bad, I could ask them to stop” was revised to “In the first few hours and days after I lost my baby, if someone said or did something that made me feel bad, I could ask them to stop” or “In the first few hours and days after I lost my baby, if someone said or did something that made me feel bad, I would ask them to stop”. (3) Item 8 “In the first few hours and days after I lost a loved one, if something happened that I did not like, I was usually able to fix it” was changed to “In the first few hours and days after I lost my baby, if something happened that made me feel sad, I was usually able to soothe my emotions and solve the problem on my own”. (4) The experts thought that the phrases “During and after my perinatal loss, I was satisfied with the way my loss was experienced because I had to go through” and “During and after my perinatal loss, I was satisfied with my interactions with the nurses” in items 11 and 14 are not in line with Chinese thinking and should be changed to “At the time of my loss and for some time afterward, I identified with my experience of losing my baby because it was a process that I had to go through” and “At the time of my loss and for some time afterward, I was satisfied with my interactions with the nurses and the care I received from the nurses” to be more helpful in understanding empathy in perinatal loss and make the statements more fluent. The final Chinese version of the PGIS included three dimensions and 14 items.

A total of 252 pregnant women with perinatal loss completed the survey in this study, and their general information is detailed in Table 1.

The correlation coefficients of each item and the total score of the scale were 0.526–0.659 (p 0.001), which all were $>$0.400, and the scores of each item were positively correlated with the total score of the scale, indicating a high correlation between each item and the scale and the items were not deleted. The CR values of the independent sample t-test for high and low groups ranged from 6.675 to 11.638, which all were $>$3.000, and the differences were statistically significant (p 0.001), indicating that the scale items were well differentiated and all items were retained.

Table 5 presents Cronbach’s alpha coefficients for the Chinese version of the PGIS. The overall Cronbach’s alpha coefficient was 0.768. Furthermore, Cronbach’s alpha coefficients for the three dimensions, namely reality, confront others, and congruence, were 0.702, 0.783, and 0.753, respectively. The split-half reliability coefficient was calculated to be 0.749.

Validity reflects the correctness and validity of the scale, and the commonly used validity evaluation indices are content validity and structural validity [11]. The CVI at the item level was 0.86–1.00 $\ge$ 0.78, and at the total scale level was 0.92 $\ge$ 0.90, indicating that the content validity of the scale was good and can effectively predict the degree of risk of post-traumatic stress disorder (PTSD) after abortion. The scale introduction process through strict translation, back translation, expert consultation, and pre-testing fully ensured the equivalence between the Chinese version of the scale and the original English scale. In addition, the structural validity of the scale was evaluated by exploratory factor analysis, and the loadings and cumulative variance contribution of each item were higher than the standard. The four metric factors extracted in this study were slightly different from the three dimensions of the original scale, which might be related to the different cultural backgrounds, fertility concepts, and lifestyles between China and the United States. The combination of male factor four and male factor three is a reflection of whether patients with perinatal loss perceive themselves as agreeable to their friends and healthcare providers, and both dimensions are compatible; thus, their combination is the same as the dimensions of the original scale.

Reliability refers to the consistency between scale items, and Cronbach’s alpha coefficient is the most commonly used measure of reliability. The results of this study showed that Cronbach’s alpha coefficient and split-half reliability of each dimension and total scale were $\ge$0.70, indicating that the items of the scale had homogeneity and good reliability [10].

Although the PGS [13] is the most commonly used standardized scale to assess post-abortion grief, it can indicate a significant increase in the intensity of perinatal grief with an increase in the number of miscarriages [14]; the PGS only detects the presence of high levels of stress or psychiatric problems in the current situation and does not provide an early prediction of severe anxiety and depression after miscarriage. Both PGS and PGIS are specific measures of perinatal loss and a history of mental illness in pregnant women experiencing a miscarriage. A history of mental illness, childlessness, unknown cause of perinatal miscarriage, limited social support, and marital/relationship discord put a woman at a higher risk for miscarriage and the development of pathology after perinatal loss [15]. Using the PGIS at the initial stage of diagnosis of unavoidable miscarriage or fetal abnormality can help identify patients who may suffer from depression or anxiety after perinatal loss [16], making them benefit from inpatient psychotherapy, medication, professional follow-up, and assessment of pregnancy spacing [17]. The time interval from awareness of risky pregnancy to two weeks after the loss is the optimal period to be assessed by the PGIS, which provides a positive effect on the psychological trajectory of post-traumatic growth within one month after discharge and helps patients to effectively cope with the 5-stage process of traumatic reaction, ruminative rumination, nostalgic farewell, positive coping, and post-traumatic growth and reduces PTSD in patients with pregnancy loss [17]. Patients with pregnancy loss develop PTSD [18], which can be identified by PGIS, indicating its significance. This scale has moderate items with simple and intuitive language and is generally completed in less than 10 min, making it functional. Using this tool can provide our healthcare professionals with an objective, quantitative, and practical method for the early identification of PTSD after perinatal loss.

The Chinese version of the PGIS demonstrates strong reliability and validity when compared to the PGS [5]. This study confirms that the PGIS [19] is capable of predicting severe anxiety and depressive symptoms in women three months after perinatal loss, when administered two weeks following the event. This finding is valuable for healthcare providers as it helps identify women who require additional mental health assessment after experiencing a miscarriage. Healthcare providers play a crucial role in addressing clinical issues related to perinatal loss [20]. This study emphasizes the importance of accurately assessing the grief experience of families, understanding the grieving process, providing professional support, enhancing coping skills, facilitating acceptance of the reality of loss, demonstrating high patient acceptance, and ultimately promoting healthy family development. However, it is important to note that this study was conducted within a single tertiary care maternal and child health hospital, limiting the generalizability of the findings to other settings. Additionally, the study did not include a multicenter approach in recruiting the study population. Furthermore, the exploratory factor analysis of the scale was performed in this study, while confirmatory factor analysis and calculations of the scale’s specificity and sensitivity were not conducted.

Perinatal fetal death is a distressing event for families, characterized by a high incidence, prolonged negative psychological effects, and a significant impact on women’s quality of life. However, the psychological aspects of grief in women experiencing perinatal loss have not received sufficient attention from clinical medical professionals in China. Limited studies have been conducted in this area, highlighting the need for more comprehensive investigations. Among medical personnel, nurses play a crucial role as they have direct contact with women affected by perinatal loss [21]. Firstly, they can encourage women to openly express their emotions and identify risk factors associated with their grief reactions. By actively listening, nurses can gain a deeper understanding of the unique grief experiences and psychological needs of this population. Secondly, nurses can provide sensitive and supportive care, implementing interventions aimed at mitigating the negative impact of perinatal loss on women, their partners, and their families. It is crucial to acknowledge and address grief in clinical practice, along with implementing targeted professional training and grief counseling for healthcare workers. Such initiatives should focus on families dealing with perinatal loss, while also assisting healthcare workers in effectively managing their own psychological well-being and experiences. Future research should incorporate confirmatory factor analysis to provide robust psychometric information about the PGIS scale, further enhancing its validity. Additionally, it is important to broaden the scope of the study population, continuously assess grief levels, and develop culturally relevant intervention models that can improve the grief experiences of women affected by perinatal loss. These efforts will enable women to actively engage in their lives following the loss and provide valuable insights for the development of grief support intervention programs within the Chinese cultural context.