Regarding characteristics of the studied nurses (Table 1), it was mentioned that less than half of nurses were in the age group 30 < 40 years, and less than two-thirds of them had technical institute of nursing educational level. This finding was agreed with [29] who carried out a study about “Nurses performance regarding humanized care of newborn with hyperbilirubinemia” and founded that two-fifths (40.0% & 41.4%) of the studied nurses were in the age group 30– < 40 years and had nursing technical institute degree, respectively. The researcher believed that this age category can easily achieve high-quality nursing care and increase the ability to tolerate the working load.

According to characteristics of the studied neonates (Table 2), it was evident that around three-quarters of the control and study groups aged from 1 to 7 days. The current study was matched with [30] who conducted a study entitled “Magnitude and its associated factors of neonatal jaundice among neonates admitted to the neonatal intensive care unit of Dessie Town public hospitals, Amhara region, Ethiopia, 2020: a multicenter cross-sectional study” and declared that more than three-quarters (75.2%) of the studied neonates aged from 1 to 7 days.

More than half of the study group was female, while less than two-thirds of the control group were female neonates. In a study titled “Exploration of the pathogenic factors of neonatal jaundice and the clinical effect of blue phototherapy,” [31] found that over half (52.5%) of the control group and over two-fifths (43.3%) of the study group were female. This result was in line with current findings.

Related to birth weight of neonates, it was found that the control group had mean 3096.6 ± 390.13 g and study group had mean 3016.7 ± 387.32 g. This finding was similar to [32] whose study was entitled “Imaging of nerve injury in neonatal acute bilirubin encephalopathy using 1H-MRS and Glu-CEST techniques” and declared that the mean birth weight of neonates in the control group was 3027 ± 301.1 g and in the study group was 3032 ± 308.3 g. Additionally, the current study was agreed with [33] whose study was entitled “High levels of pathological jaundice in the first 24 h and neonatal hyperbilirubinemia in an epidemiological cohort study on the Thailand-Myanmar border” and found that the mean birth weight of the studied neonates was 3001 ± 420 g.

According to neonates’ type of delivery, it was evident that more than half of both control and study groups were born by cesarean section. This result was agreed with [34] who conducted a study about “Comparison of the effect of foot reflexology and body massage on physiological indicators and bilirubin levels in neonates under phototherapy” and found that the half (50%) of control and study groups were born by cesarean section. On the other hand, the study was disagreed with [35] who conducted a study about “Epidemiology of neonatal jaundice at Punakha District Hospital, Punakha, Bhutan” and revealed that the majority (86.7% & 98.9%) of control and study groups, respectively, were born by normal delivery.

As regards neonates’ type of feeding (Fig. 1), less than three-quarters of the studied neonates in the control and study groups were artificially fed. This finding was agreed with [36], whose study was entitled “Assessment of behavioral and neurological responses of neonates with jaundice undergoing phototherapy” and reported that the majority (90.0%) of the studied neonates were artificially fed. In the same line, the current study consisted with [37], whose study was entitled “Evaluating protocol of management of unconjugated hyperbilirubinemia in neonatal intensive care unit at Qena University Hospital” and showed that more than two-thirds (69.4%) of the studied neonate were artificially fed. From the researcher point of view, this result is due to neonates in NICUs being temporary separated from their mothers plus neonates with pathological jaundice facing effort from breastfeeding.

Regarding neonates’ medical history (Table 3), the current study showed that pathological jaundice caused by RH incompatibility (mother with negative RH) represented less than two-fifths of the study group. This result was in harmony with [38] who conducted a study entitled “Effect of phototherapy on eosinophils count in neonatal hyperbilirubinemia (cross-sectional study)” and found that more than two-fifths (44.5%) of the study neonates had pathological jaundice due to RH incompatibility. From the researcher point of view, these results can be attributed to lack of proper antenatal care and lack of awareness of general population.

Additionally, the current study showed that pathological jaundice caused by sepsis represented less than one-fifth in control and study groups. This result was congruent with [39] who conducted a study entitled “Neonatal jaundice: its determinants among neonates admitted to neonatal intensive care units of Tigray region general hospitals, Northern Ethiopia” and reported that less than one-fifth (18.3%) of the neonates had pathological jaundice due to sepsis. Meanwhile, the current study was disagreed with [40] who conducted a study entitled “Incidence and patterns of neonatal jaundice in tertiary medical facility” and revealed that the minority (4.9%) of the neonate had pathological jaundice due to sepsis. From the researcher point of view, lack of hygiene during and after delivery, poor cord care, and unhygienic newborn care practices may be the major factors in acquisition of neonatal infections and sepsis which caused pathological jaundice.

According to bilirubin level on admission before the use of bilisphere phototherapy, the current study showed that less than two-thirds of control and study groups reached 10 < 20 mg/dL. This finding was matched with [41] who conducted a study entitled “Effectiveness of conventional phototherapy, intensive phototherapy and exchange transfusion in treating neonatal jaundice at Fatima Al-Zahra Hospital for maternity and children in Baghdad” and found that the majority of the studied neonates (83.6%) in the bilirubin level reached 10–19 mg/dL before the use of bilisphere phototherapy.

Regarding studied subjects blood groups, less than one-third and more than one-third of mothers had (O) blood group in control and study groups. In addition, none and the minority of neonates had (O) blood group in control and study groups which explained the result of less than one-third of control and study groups with ABO incompatibility. This result was not matched with [42] who found that around one-third (39.7% & 31.4%) of mothers and neonates, respectively, had (O) blood group and explained the minority (8.3%) of neonates had pathological jaundice due to ABO incompatibility. From the researcher point of view, this result proved the fact of ABO incompatibility which caused by mother with (O) blood group and had neonate with other blood group: A, B, or AB.

As regards studied subjects RH, more than one-third of mothers had negative RH in control and study groups. Additionally, all neonates in control and study groups had positive RH which explained the result of more than one-third of control and study groups with RH incompatibility. This result was not matched with [42] who carried out a study entitled “Assessment of neonatal nurses’ performance regarding early detection of neurological dysfunction among neonates having hyperbilirubinemia” and reported that less than two-thirds (63%) of mothers had negative RH and around two-thirds (66%) of neonates had positive RH which explained less than two-thirds (63%) had pathological jaundice due to RH incompatibility. From the researcher point of view, this result proved the fact of RH incompatibility which caused by mother with negative RH and had neonate with positive RH.

The present study found that most of the nurses under investigation had adequate knowledge about pathological jaundice and bilisphere phototherapy, following the implementation of the education program, based on their overall knowledge of these topics (Fig. 2). This result was consistent with a study by [43] titled “Enhancing neonatal nurses’ performance regarding early detection of neurological dysfunction among neonates having hyperbilirubinemia.” The study found that less than three-quarters (70%) of the nurses studied knew enough about pathological jaundice and how to manage it after implementing an education program. Furthermore, the current study indicated that most nurses (86%) had sufficient knowledge after the intervention, which is in agreement with [44]. This result highlights the significance of conducting a nursing education program because, from the perspective of the researcher, nurses with sufficient knowledge may be able to inform the caregivers and assist in debunking some myths, sociocultural beliefs, and misconceptions regarding neonatal pathological jaundice and bilisphere phototherapy.

Regarding total score of nurses’ practice regarding care for neonates undergoing bilisphere phototherapy (Fig. 3), the current study revealed that the majority of the studied nurses had competent level of total practice, post-education program implementation compared to more than two-thirds pre-education program implementation. This finding was agreed with [45] who conducted a study entitled “Effect of applying aluminum foil reflector during phototherapy combined with nursing care on neonatal hyperbilirubinemia” and found that the majority of the studied nurses (88.3%) had competent level of practice post-intervention program implementation. On the other hand, the current study was not matched with Galala et al. (2023) and declared that more than two-thirds (68.3%) of the studied nurses had incompetent level of total practice pre-program implementation. Additionally, the current study was unharmonious with [46] and showed that more than three-quarters (76.2%) of the studied nurses had incompetent level of total practice pre-program implementation. From the researcher point of view, this finding could be attributed to the absence of continuing educational and training programs at NICU regarding bilisphere phototherapy in different hospitals. Meanwhile, Benha Specialized Pediatric Hospital emphasized training program to nurses towards different diseases.

According to neonates’ medical assessment (Table 4), the current study revealed that the intended range of total serum bilirubin test was achieved in more than two-thirds of the neonates’ studied group. This result was matched with [47] who conducted a study entitled “Intensive phototherapy as the initial management of severe hyperbilirubinemia in neonates: A literature review” and reported that less than two-thirds (64%) of the neonates’ studied group had better value of bilirubin after intensive phototherapy. From the researcher point of view, bilisphere phototherapy had an effective role to control bilirubin level immediately after exposure.

The study and control groups showed a highly statistically significant difference in bilisphere phototherapy side effects (P ≤ 0.001). This outcome was consistent with a study by [48] titled “Conventional intensive versus LED intensive phototherapy oxidative stress burden in neonatal hyperbilirubinemia of hemolytic origin” which found that the bilisphere phototherapy group experienced significantly higher rates of skin rash, dehydration, and hyperthermia (P = 0.02). From the perspective of the researcher, it is crucial to remember that phototherapy has saved many lives and avoided several cases of serious brain injuries, despite all of its possible hazards and adverse consequences.

As regards neonates exchange transfusion, the current study revealed that the minority of the study group need exchange transfusion after use of bilisphere phototherapy. This result was matched with [49] who founded a study entitled “Intensive 360°(Capsule) versus Conventional Phototherapy in Neonatal Jaundice” and reported that the minority (10.4%) of neonates need exchange transfusion after use capsule phototherapy. Additionally, the current study was congruent with [50] whose study was entitled “Neonatal jaundice: magnitude of the problem in Cairo University's neonatal intensive Care unit as a referral center” and found that the minority (six cases 0.7%) of neonates used intensive phototherapy and exchange transfusion together. From the researcher point of view, this result confirmed the recommendations of the American Academy of Pediatrics (2004) which showed performing exchange transfusion for full-term newborns at least 4 days of age if their TSB level is 25 mg/dL or more and does not decrease sufficiently with phototherapy alone.

According to neonates’ neurological status and the severity of pathological jaundice (Table 5), the current study illustrated that more than one-fifth had mild bilirubin encephalopathy, and the minority had moderate bilirubin encephalopathy of neonates’ study group. This result was in the same line with [50] who found that the minority (2.9%) of neonates’ study group had moderate bilirubin encephalopathy. On the other hand, the current study was inconsistent with [51] who conducted a study entitled “Impact of intensive phototherapy on neurological state of neonates with severe hyperbilirubinemia” and found that after intensive phototherapy, neonates with mild and moderate BIND showed 97.5% and neonates with severe BIND score had persistent evidence of BE (2.5%). From the researcher point of view, BIND score is an important tool to assess neurological status of neonates with pathological jaundice, so early neonates management with bilisphere phototherapy protect neonates from neurological complications and BE.

Regarding health outcomes of neonates immediately after discharge from bilisphere phototherapy (Fig. 4), the current study revealed that the majority of neonates in the study group had improvement immediately after discharge from bilisphere phototherapy compared to less than three-quarters in the control group. This result was congruent with [41] whose study was entitled “Effectiveness of conventional phototherapy, intensive phototherapy and exchange transfusion in treating neonatal jaundice at Fatima Al-Zahra Hospital for maternity and children in Baghdad” and found that the majority (92%) of neonates had successful improvement after intensive phototherapy. Additionally, the current study was supported with [52] who conducted a study entitled “Outcome of neonatal jaundice at Fatima Al-Zahra Hospital for maternity and children in Baghdad” and showed that the majority (99.3%) of the neonates had improvement immediately after discharge from bilisphere phototherapy. On the other hand, the current study was inconsistent with [53] who conducted a study entitled “Predictors of neonatal hyperbilirubinemia's outcome and their relationships to the etiology” and reported that more than three-quarters (75.8%) of the neonates had improvement immediately after discharge from bilisphere phototherapy. From the researcher point of view, bilisphere phototherapy is an important device which had positive outcomes in pediatrics which improve neonates’ health status, but its effect depends on provided effective nursing practice during therapy.

Regarding the correlation between the nurses’ overall knowledge and practice of bilisphere phototherapy (Table 6), the current study showed that both before and after the implementation of the education program, there was a positive correlation between the nurses’ total knowledge and practice of bilisphere phototherapy. This finding was consistent with [44], who discovered a very statistically significant association (r = 0.39) between the nurses’ post-intervention total knowledge and practices regarding neonatal hyperbilirubinemia. Similarly, [54] conducted a study titled “A study to assess the effectiveness of protocol on care of newborn in phototherapy on knowledge and practice among nurses at selected hospitals in South India” and found a strong correlation (r = 0.80) between nurses’ overall mean improvement level of knowledge and practices regarding newborn care in phototherapy.

Regarding correlation between neonates’ outcomes in the study group and nurses’ total knowledge and practice, post-education program implementation (Table 7), the current study represented that there were a positive correlation between neonates’ outcomes in the study group and nurses’ total knowledge and total practice regarding bilisphere phototherapy at post-education program implementation. This result was congruous with [42] who reflected that there were highly statistical significant positive correlations between nurses’ total knowledge, total practices, and neonates’ outcomes which it was found that the higher the level of nursing practices, the fewer the frequency of side effects of phototherapy. From the researcher point of view, equipping nurses with knowledge and practice and maintaining updates with professional training provide high quality of neonate care.

A few limitations applied to this study: there are significant regional differences in the pattern of etiological variables for neonatal pathological jaundice. Our findings may not be indicative of the trend in other regions as a result. Only English-language publications were included in our inquiry; thus, we probably missed some important studies, especially those pertaining to Chinese, Turkish, and traditional medicine.