This study aimed to investigate the efficacy of PERMA-based nursing intervention in reducing the fear of disease progression in parents of children with acute leukemia. A quasi-experimental design was employed, enrolling children with acute leukemia and their parents at the First Hospital of Jilin University, who were divided into intervention and control groups. The intervention group received an 8-week positive nursing intervention covering eight themes, including positive self-awareness, emotion regulation, and cultivation of positive qualities. The control group received standard nursing care. Results indicated that after the intervention, the total fear of parental disease progression scores in the intervention group were significantly lower than those in the control group, and the positive psychological capital scores were significantly higher. Additionally, the scores for positive coping strategies also significantly increased. This study confirmed the effectiveness of PERMA-based positive psychological intervention in enhancing the psychological capital and happiness of parents of children with acute leukemia, providing a new perspective for clinical psychological nursing.

• PERMA model
• Nursing intervention
• Acute Leukemia
• Fear of Progression
• Psychological Capital

Li X, Cao S, Zhang Y, Guo F (2024) The Eficacy of PERMA-Based Nursing Intervention on Reducing Fear of Disease Progression in Parents of Children with Acute Leukemia: A Quasi-Experimental Study. J Hematol Transfus 11(2): 1124.

In recent years, the incidence of childhood cancer has increased and has become the second leading cause of death threatening the life and health of children [1,2]. It is estimated that there will be 6 -7 million cases of childhood cancer [3] worldwide between 2015 and 2030. In China, the incidence of childhood leukemia ranks first, accounting for 32.89% of all new tumors, of which more than 90% are acute leukemia [4]. With the improvement of medical technology, the survival period of children with acute leukemia has been continuously extended continuously, and their 5-year survival rate is more than 85% [5]. However, the cancer treatment cycle is long, and it has the characteristics of easy metastasis and recurrence. A cohort study reported that the recurrence rate of children with cancer ranged from 2.4% to 9.4% within 20 years, and the proportion of the second cancer within 30 years ranged from 7.2% to 12.1 [6]. Parents, as the main caregivers and medical decision makers, are prone to fear of disease progression due to long-term concern about cancer recurrence or poor prognosis.

Fear disease progression refers to the various biological, psychological, social consequences, or the recurrence of fear disease [7]. Herschbach FoP considers that two states [8] include functional level and dysfunctional level. FoP is at the functional level, and the parents are able to adopt positive coping behaviors when facing the threats and challenges posed by the disease. However, several studies have shown that parents of children with cancer often have FoP dysfunction, and the incidence of FoP varies from 48.3% to 81% [9,10]. Yang et al., showed that up to 75.1% of parents were in FoP dysfunctional [11]. Clever et al found that 61.9% of the parents had severe FOP [12]. Peiker et al., showed that 54% of mothers and 41% of fathers developed severe FOP [13]. Continuous and strong FoP not only seriously affects the physical and mental health of parents, reduces their quality of life and happiness, but also hinders children and parents to return to normal family life, and eventually leads to impaired family function [14]. In addition, parents with FoP dysfunction are highly alert and worried about their children's physical symptoms, which leads to excessive protective behavior of parents, and then affects the behavior, social and emotional regulation ability of children, which is not conducive to the disease recovery and physical and mental health of children [11]. It can be seen that medical staff should attach great importance to parents with FOP dysfunction and provide timely help. A standard for psychological care for parents of children with cancer also points out that [15], in the process of disease diagnosis and treatment and care of children, medical staff should also assess the mental health needs of their parents, and timely intervene in the psychological problems of parents. Therefore, how to help parents of children with acute leukemia reduce the fear of disease progression and improve psychological capital and happiness has become an urgent problem to be solved.

With the development of bio-psychological-social modern medical model, clinical medical staff not only pay attention to the recovery of physiological function, but also pay attention to mental health. With the rise of positive psychology, positive psychological intervention (positive psychological intervention, PPI) has attracted wide attention and attention. The American psychologist Martin Seligman first proposed the PERMA theoretical model in 2011, which consists of positive emotion, engagement, relationship, meaning and achievement. He believes that positive psychology can find the internal resources such as human positive forces and excellent qualities, so as to maximize their own potential to obtain a better life [16]. The PERMA model provides a new perspective for researchers to focus on individual psychology, which has been applied in the [17] of chronic [17,18] for medical staff and [19] for the elderly, and has achieved significant results [20]. Several studies have proved that in [21-23] positive psychological intervention can reduce individual negative emotions, improve the quality of life and subjective well-being, maintain mental health, and promote health behaviors. Thus, positive psychological interventions may help to promote the mental health of the parents of children with acute leukemia. Future research should not be limited to the discovery of individual psychological problems, but should pay more attention to solving negative problems on the basis of exploring individual positive psychological qualities and mobilizing positive emotions, so as to realize the transformation from traditional psychology to positive psychology.

At present, there are few interventional studies on the parents of children with acute leukemia, and it has not attracted the attention of clinical medical staff. Therefore, this study discusses the psychological intervention based on PERMA model of children with acute leukemia parents FoP, positive psychological capital, coping style, happiness, is conducive to guide more researchers attention to positive psychological intervention practice, aims to improve the parents fear of disease progress at the same time, improve the psychological capital and happiness, eventually promote the recovery of disease and physical and mental health.

Study design

The study is a quasi-experimental study with pre- and post- test control groups. Children with acute leukemia (AL) admitted to the First Hospital of Jilin University and their parents were recruited to participate in the study and were divided into control and intervention groups based on their admission time.

Characteristics of participants

The study included children with AL and parents who met the following inclusion criteria: (i) Children diagnosed with leukemia (including lymphocytic, non-lymphocytic, and other types of leukemia) through bone marrow aspiration, aged ≤14 years; (ii)The child's parent or mother who is the primary caregiver, spending at least 4 hours per day with the child, at least 5 days a week; (iii) Parents' fear of disease progression scale score ≥34 [24], reaching a clinically significant level, i.e., defined as FoP positive;(IV)The child's parents have no communication barriers and can understand the content of the questionnaire;(V)Informed consent to participate in this study and willing to sign a privacy protection agreement.Exclusion criteria: (i) Previous history of mental illness or severe cognitive impairment; (ii) Patients with other major physical illnesses at home; (iii) Parents of children who refuse to participate in this study or participate in other studies;(iv) Parents of children who fail to complete this study.

Establishment of Positive Care Group

The team consists of a hematologist, a psychological consultant, a practicing nurse, a pediatric nursing expert, and two nursing graduate students. The hematologist is responsible for diagnosing and treating diseases and providing professional guidance for the thematic group in the study; the psychological consultant mainly guides the thematic group on psychosocial knowledge; the specialist nurse is in charge of guiding the nursing knowledge and skills of the thematic group as well as empowerment education; the nursing graduate students are responsible for the preliminary development of the main content of the positive nursing intervention plan, and participate in the positive nursing intervention for the parents of the children patients with the specialist nurse, and are responsible for recording the progress of the intervention implementation and collecting information. Before the implementation of the project, the team members involved in the positive nursing intervention received training and became familiar with the content, process, and key points of implementation of the positive nursing intervention plan.

Implementation of the intervention

The intervention group implemented an 8-week positive care intervention conducted in the form of face-to-face communication interviews. The main components of the program were first determined by the researchers based on literature reviews and group meetings to understand the care needs of caregivers, and then reviewed and revised by team members. It mainly covered eight themes including positive self-awareness and care, positive regulation of negative emotions, cultivation of positive qualities, "Spring Blooms", "Focus", "Unity and Mutual Assistance", "Giving Roses, Scent on Hands", and "Where there is a will, there is a way". Intervention Location: Pediatric Hematology Ward. Based on the results of the preliminary experiment and the actual situation of the parents of children with leukemia, targeted positive nursing interventions were developed (for specific content, see Table 1).

Table 1: Positive nursing intervention program

Control group

Within the pediatric hematology unit, standard nursing care is meticulously designed to address the multifaceted needs of parents with children undergoing treatment for leukemia. This care includes an educational component focused on imparting knowledge about the disease, its treatment, and prognosis, ensuring that parents are well-equipped to understand and manage their child's health journey. Dietary counseling is provided to support the nutritional well-being of the child, recognizing the critical role of nutrition in recovery and overall health. Medication guidance is tailored to help parents administer prescribed therapies effectively, emphasizing the importance of compliance for treatment success. Psychological Nursing is integral, aiming to mitigate the stress and anxiety inherent in caring for a child with a serious illness, thus fostering a supportive environment that nurtures both the child's and family's emotional health.

General information questionnaire

Designed based on literature review, our questionnaire captures two main areas: pediatric demographics—including gender, age, and medical details such as nutritional status and treatment phase—and parental profiles, encompassing relationship to the child, age, education, and economic status, as well as medical payment methods.

Fear of Progression Questionnaire-Short Form/ Parent Version (FoP-Q-SF/PR)

The FoP-Q-SF/PR was developed by Schepper et al. [25], in 2015, is a 12-item instrument comprising three dimensions: emotional reactions, family life, and school life. It utilizes a 5-point Likert scale, ranging from "never" to "always," with total scores between 12 and 60; higher scores indicate greater fear of disease progression in parents of pediatric cancer patients. The questionnaire demonstrates robust reliability and validity, with a Cronbach's α of 0.893 and a 3-week test-retest reliability of 0.819, and dimension-specific α coefficients ranging from 0.819 to 0.858 [26]. Herschbach et al. [24], suggest a threshold of ≥34 for identifying severe FoP, indicative of functional impairment.

Simplified Coping Style Questionnaire (SCSQ)

The SCSQ adapted by Xie Ying [27] for Chinese culture, is a 20-item scale with two dimensions: positive and passive coping. It uses a 4-point Likert scale, ranging from "never used" (0 points) to "frequently used" (3 points). The SCSQ demonstrates high reliability, with a total scale Cronbach's α of 0.90, and subscale α coefficients of 0.89 for positive coping and 0.78 for passive coping.

Positive Psychological Capital Questionnaire (PPQ)

The PPQ developed by Zhang Kuo et al. [28], in 2010, assesses four dimensions: self-efficacy, resilience, hope, and optimism, with a total of 26 items. Rated on a 7-point Likert scale from "completely disagree" to "completely agree," the PPQ includes reverse-scored items [8,10,12,14,25] with total scores ranging from 26 to 182; higher scores indicate greater positive psychological capital. The questionnaire has a Cronbach’s α of 0.902, with all item factor loadings above 0.5, reflecting sound internal consistency and construct validity.

Index of Well-Being (IWB)

The IWB translated and adapted by Fan Xiaodong in 1999 [29], assesses the subjective well-being of parents of pediatric patients. It comprises two sections: The Total Affect Index (8 items) and the Life Satisfaction Questionnaire (1 item). Utilizing a 7-point Likert scale, the total score is calculated by summing the average of the Total Affect Index and the weighted score (1.1) of the Life Satisfaction Questionnaire. Scores range from 2.1 to 6.0 for low well-being, 6.1 to 10.0 for moderate well-being, and above 10.0 to 14.7 for high well-being. The IWB demonstrates a Cronbach’s α of 0.90, indicating high reliability.

Data Collection

Participants were selected based on strict inclusion and exclusion criteria. Prior to questionnaire administration, the purpose and significance of the study were explained to potential participants, who then provided informed consent. Data collection was conducted by the principal investigator using both paper and electronic formats (Questionnaire Star) at three time points: pre-intervention, immediately post-intervention, and one month post-intervention.

Statistical Analysis

Data were analyzed using SPSS 27.0 software, with statistical significance set at P < 0.05. Descriptive statistics for continuous variables were presented as mean ± standard deviation (x±s), while categorical data were expressed as frequencies and percentages. For between-group comparisons, independent t-tests were utilized. Within-group comparisons at pre- intervention, immediately post-intervention, and one month post-intervention were assessed using repeated measures ANOVA, with Mauchly's test for sphericity and Greenhouse- Geisser correction applied where necessary.

Baseline characteristics

According to the inclusion and exclusion criteria, a total of 64 children were initially included in this study, 32 in the intervention group and 33 in the control group. The basic information of the children is shown in Table 1. The comparison of demographic characteristics between the two groups was not statistically significant (P > 0.05), indicating a balanced comparability, as shown in Table 2.

Table 2: Participants’ demographics

Main outcomes

The results showed that after one month of intervention, the Total Fear of Parental Disease Progression Scores were significantly lower in the intervention group than in the control group, with statistically significant differences (P<0.001). The one month post-intervention score in Total Fear of Parental Disease Progression Score was 16.31±2.07 in the intervention group and 28.38±3.97 in the control group, which was statistically significant. The time effect, group effect and interaction effect between the two groups were statistically different (P<0.05) on all dimensions [Table 3 and 4].

Table 3: Comparison of Participants’ demographics between the two groups

Table 4: Fear of Disease Progression Score of Parents of Children in Both Groups

After the intervention, the total Positive Psychological Capital Scores of the intervention group was significantly higher than that of the control group, and the group effect was statistically significant (P<0.05). The self-efficacy scores in total Positive psychological Capital Scores was higher in the intervention group than in the control group, and the time effect in this dimension was statistically significantly higher (P<0.001). However, the group effect differences between the two groups on the self- effect, resilience ,optimism and desire dimensions were not statistically significant (P>0.05) [Table 5 and 6].

Table 5: ANOVA of repeated measures of parents' fear of disease progression in the two groups of children before and after the intervention

Table 6: Positive psychological capital scores of parents of children in both groups

The results of the study show that before the intervention, the total subjective well-being index scores of the two groups were at similar levels, and after intervention, intervention group scores improved more than control group, and the differences in all three effect dimensions have statistically significant(P<0.05) [Table 7 and 8].

Table 7: Repeated Measures ANOVA for Positive Psychological Capital of Parents of Children in Both Groups

Table 8: Subjective well-being index scale scores of parents of children in both groups

According to the results, we find that before intervention. The Total Scores of the Simplified Coping Style Questionnaire in intervention group is 29.53±4.85 and is 30.19±4.37 in control group, and after one month intervention, is 43.22±4.26 in intervention group and 33.69±3.46 in control group, respectively. The results of this two groups comparison showed that the intervention group had higher the Simplified Coping Style Questionnaire scores after intervention than the control group, and the data has a statistically significant difference(p<0.001). The differences of positive coping and passive coping between the two groups also have a statistically significant (p<0.05) [Tables 9,10 and 11].

Table 9: Repeated measures ANOVA of the index of subjective well-being of parents of children in the two groups before and after the intervention.

Table 10: Scores of the Simplified Coping Style Questionnaire of parents of children in both groups

Table 11: Repeated Measures ANOVA for Parent's Simple Coping Score for both groups of children

Positive Psychological Capital

Our study demonstrated that following the PERMA-based nursing intervention, the experimental group exhibited a significant enhancement in positive psychological capital compared to the control group. Specifically, improvements were observed across all dimensions of positive psychological capital, including self-efficacy, resilience, hope, and optimism, with statistically significant differences between the experimental and control groups post-intervention.

The findings of our study are in line with those of previous research. For instance, Eilertsen et al. [30], reported that positive psychological interventions can bolster psychological resilience and optimism levels among parents of children with leukemia. Additionally, Seligman's [31] research on positive psychology interventions suggests that they can strengthen an individual's positive psychological capital, which corroborates our findings of increased positive psychological capital among the parents in the experimental group.

The increase in positive psychological capital may be attributed to the cultivation of positive emotions and engagement within the PERMA model. The nurturing of positive emotions is likely to enhance self-efficacy and hope, while engagement and achievement may reinforce resilience and optimism. These factors, when combined, contribute to an overall elevation in positive psychological capital.

To further augment the positive psychological capital of parents of children with acute leukemia, several strategies are recommended. Firstly, healthcare professionals should offer more activities aimed at fostering positive emotions, such as emotional management workshops and positive psychology educational courses. Secondly, parents should be encouraged to participate positively in their child's care to enhance their sense of self-efficacy and achievement. Drawing on Snyder's [32] theory of hope, setting concrete and attainable goals can improve parents' hope levels. Lastly, optimism can be cultivated through cognitive restructuring techniques, assisting parents in interpreting and coping with challenges in a more positive light.

Coping Strategies

In our investigation, the application of the PERMA-based nursing intervention resulted in a significant improvement in coping strategies among parents of children with acute leukemia. The experimental group demonstrated a marked increase in positive coping behaviors post-intervention, as indicated by the Simplified Coping Style Questionnaire (SCSQ) scores, which were notably higher than those of the control group.

Our findings are in agreement with those of previous studies that have shown positive psychological interventions can lead to more adaptive coping mechanisms in caregivers. For instance, research by Compas et al. [33], highlighted the importance of positive coping strategies in reducing psychological distress among parents managing their children's health conditions.

The enhancement in positive coping strategies observed in our study can be attributed to the PERMA model's focus on fostering positive relationships and a sense of meaning and accomplishment. These elements encourage parents to adopt more propositive and constructive approaches to dealing with the challenges associated with their child's illness.

To further improve coping strategies among parents of children with leukemia, it is suggested that healthcare providers offer structured interventions that emphasize skill-building in positive coping. This could include workshops on stress management, communication skills, and problem-solving techniques. Additionally, fostering a supportive community for parents can provide a platform for sharing experiences and coping strategies, which is supported by studies showing the benefits of social support on coping and mental health outcomes [34].

Fear of Progression

The current study revealed that the Fear of Disease Progression (FoP) among parents of children with acute leukemia was significantly reduced following the implementation of the PERMA-based nursing intervention. Post-intervention assessments indicated a substantial decrease in FoP scores in the experimental group compared to the control group, demonstrating the efficacy of the intervention in alleviating parental concerns regarding disease progression.

Our results are consistent with those of studies that have explored the impact of psychological interventions on FoP in parents of children with chronic illnesses. For example, a study by Yang et al. [35], found that psychological interventions can effectively reduce fear of progression in parents of children undergoing cancer treatment, which is in line with our findings.

The reduction in FoP observed in our study can be attributed to the multifaceted approach of the PERMA model, which not only addresses the emotional well-being of parents but also provides them with a sense of control and understanding of their child's disease. This comprehensive support likely contributes to a decrease in uncertainty and fear regarding the disease's progression.

To further mitigate FoP among parents of children with leukemia, it is recommended that healthcare providers continue to incorporate comprehensive psychological support into their care plans. This could involve regular sessions with psychotherapists, access to peer support groups, and educational workshops that empower parents with knowledge about their child's condition and effective coping strategies. Additionally, fostering an environment where parents feel heard and validated can significantly reduce their fear and anxiety, as suggested by Kearney et al. [36], in their guidelines for psychosocial care for parents of children with cancer.

Subjective Well-Being

Our study demonstrated that the subjective well-being of parents of children with acute leukemia significantly improved following the PERMA-based nursing intervention. The intervention group showed higher scores on the Index of Well-Being (IWB) when compared to the control group post- intervention, indicating a positive impact on the parents' overall emotional state and life satisfaction.

The enhancement in subjective well-being observed in our study is supported by similar research in the field. For example, a study by Diener et al. [37], emphasized the importance of positive emotions and social relationships in enhancing well-being, which aligns with the PERMA model's focus on these areas.

The improvement in subjective well-being can be attributed to the PERMA model's comprehensive approach to enhancing positive emotions, engagement, relationships, meaning, and accomplishments. By targeting these areas, the intervention likely helped parents to experience more positive emotions, feel more engaged in their child's care, strengthen their social connections, find meaning in their challenging situation, and achieve a sense of accomplishment in their parenting role.

To further enhance the subjective well-being of parents of children with leukemia, it is recommended that healthcare providers continue to integrate positive psychology interventions into their practice. This could include providing resources for parents to engage in activities that promote positive emotions, such as mindfulness-based stress reduction programs, support groups to foster social connections, and educational workshops to help parents find meaning and purpose in their caregiving journey. Additionally, encouraging parents to set and achieve small, meaningful goals can contribute to a sense of accomplishment and overall well-being, as suggested by Fredrickson [38] in her broaden-and-build theory of positive emotions.

Positive nursing intervention under the PERMA model can improve the positive psychological capital and positive coping style of parents of children with acute leukemia, reduce the level of fear disease progression, and enhance subjective well-being.

Research innovation

? This study designed a set of applicable positive nursing intervention program for FoP, parents of children with acute leukemia, to provide a reference for FoP remission of parents of children with acute leukemia.

? The purpose of this study is to investigate the effects of PERMA-based positive nursing intervention on parents' positive psychological capital, benefit finding level, perceived stress, fear of cancer recurrence, and subjective well-being of children with acute leukemia, which are rarely studied in China.

? Parents of children with acute leukemia have a high incidence of FoP, and the existing interventions of FoP for parents of children with acute leukemia focus on the elimination of negative emotions, and do not consider how to explore potential positive qualities. Therefore, it is necessary to apply positive psychology to improve the positive psychological capital and coping style of the parents, so as to reduce the level of fear and disease progression and enhance well-being.

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