The Effects of Vitamin D Supplementation on Glycemic Control in Children With Type 1 Diabetes Mellitus in Gaza Strip, A Randomized Controlled Trial
Phase: NA
Conditions: Type 1 Diabetes Mellitus, Vitamin D Deficiency
Sponsor: Al-Azhar University

 
 
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Title: 
The Effects of Vitamin D Supplementation on Glycemic Control in Children with Type 
1 Diabetes Mellitus in Gaza Strip, A Randomized Controlled Trial. 
Authors: 
Heba AbdAllah Al Sarraj1, Ashraf Jaber Shaqaliah1, Heba Mohammed Arafat2, Ohood 
Mohammed Shamallakh3, and Kholoud Mohammed Shamallakh3. 
 
Affiliations: 
1 Department of Laboratory Medicine, Al Azhar University-Gaza, Gaza Strip, 
Palestine; hebasarraj24@gmail.com; ashshaq@yahoo.com. 
2 Department of Chemical Pathology, School of Medical Sciences, Health Campus, 
Universiti Sains Malaysia, Kubang Kerian, Kelantan, Malaysia; hebaarafat4@usm.my. 
3 Department of a Medical Laboratory Sciences, Faculty of Health Sciences, Islamic 
University 
of 
Gaza, 
Gaza 
City, 
Palestine; 
oho.od@hotmail.com; 
loody89@windowslive.com. 
 
Running title: 
Vitamin D Supplementation and Glycemic Control Improvement among Type 1 
Diabetic Children. 
 
Corresponding Author: 
Heba Mohammed Arafat 
Department of Chemical Pathology, School of Medical Sciences, Health Campus, 
Universiti Sains Malaysia, Kubang Kerian, Kelantan, Malaysia. 
Email: hebaarafat4@usm.my. 
Phone Number: +972599575745.  
 
Document Date: October 27, 2021 
 
 
 
 
 
 

 
 
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Abstract  
Objective: To screen for vitamin D deficiency, and to examine the effects of vitamin 
D supplementation on glycemic control among children with Type 1 Diabetes Mellitus 
(T1DM). 
Material and Methods: A randomized clinical trial including 80 children (40 
interventions and 40 controls) who were diagnosed with T1DM. Vitamin D status and 
glycated hemoglobin (HbA1c) were assessed initially for both groups. The intervention 
group was on (2000 IU/day) of vitamin D3 for 3 months while the control group did not 
receive any type of supplements throughout the intervention period. Vitamin D and 
HbA1c were measured at the baseline and the end of the study. Differences in mean±SD 
of vitamin D and HbA1c were assessed before and after the study. 
Results: A high prevalence of vitamin D deficiency (43.8%) and insufficiency (52.5%) 
was found among children with T1DM. Mean baseline serum 25-hydroxyvitamin D 
(25(OH)D) (ng/ml) increased from 14.76±3.71 to 12.46±4.35 and 38.79±16.86 to 
14.88±4.73 in both the intervention and control groups, respectively. Mean baseline 
HbA1c (%) was 10.23±1.95 in the intervention group and 9.86±2.19 in the control group. 
After vitamin D supplementation for three months, mean HbA1c (%) was 9.20±1.50 in 
intervention and 10.28±1.77 in the control group without statistically significant 
difference P>0.05 between groups. 
Conclusions: Our study revealed that in T1DM children, vitamin D deficiency 
coincided with poor glycemic control. The levels of HbA1c showed no statistically 
significant difference between children who received vitamin D supplementation and 
those who have not received it regarding glycemic control, whereas the results were 
clinically significant. 
 
Keywords: Vitamin D Supplementation, Glycemic Control, Type 1 Diabetes Mellitus, 
Gaza Strip, Randomized Controlled Trial. 
 
 
 
 

 
 
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1. Introduction 
Type 1 diabetes mellitus (T1DM) is an immune-mediated disease characterized 
by diminished insulin secretion due to damage to islets of Langerhans in the pancreas, 
which eventually results in high levels of glucose in the blood (Katsarou et al., 2017). 
According to World Diabetes Foundation, in Palestine, 4.4% of diabetic patients are 
diagnosed with T1DM, while 95.3% are diagnosed with type 2 diabetes (T2DM) 
(World Diabetes Foundation, 2020). 
Vitamin D, also known as calciferol, exists in two major forms, namely vitamin 
D2 or ergocalciferol and vitamin D3 or cholecalciferol, which are mainly found in plant 
and animal products, respectively (Busta, Alfonso, & Poretsky, 2011; Griz, Bandeira, 
Gabbay, Dib, & Carvalho, 2014). Cholecalciferol can also be synthesized in the skin 
through ultraviolet B radiation (Busta et al., 2011). The inactive forms of vitamin D are 
transported to the liver where they are hydroxylated and converted into 25-
hydroxyvitamin D (25(OH)D) or calcidiol. Thereafter, calcidiol is converted to the 
biologically active form of the vitamin, 1,25-dihydroxy vitamin D (1,25(OH)2D) or 
calcitriol (Mitri & Pittas, 2014).  
In recent years, the extra-skeletal effects of vitamin D (25(OH)D) have raised 
considerable interest since specific receptors have been found in many tissues and 
systems, including pancreatic β cells and immune cells. 25(OH)D deficiency represents 
a major health problem since it has been related to cardiovascular, inflammatory, 
autoimmune diseases, cancer, and T1DM (Savastio et al., 2016).  
Observational studies have reliably provided evidence that T1DM patients with 
acceptable glycemic control have higher 25(OH)D levels than T1DM with lesser 
glycemic control (Al Sawah, Compher, Hanlon, & Lipman, 2016; Lamichhane et al., 
2015). Additionally, it has been specified by some of the research-based studies that 
there is a strong connection between the deficiency of vitamin D and the incidence of 
T1DM (Al-Agha & Ahmad, 2015; Elhamalawi, 2015; Savastio et al., 2016).  
In interventional studies of T1DM children and adults, repletion of vitamin D 
in deficient individuals improved HbA1c in a period of 12 weeks. Participants were 
more likely to achieve HbA1c < 7.8% if they had higher 25(OH)D levels on week 12 
than on baseline, especially if 25(OH)D levels were exceeded 51 nmol/l (Aljabri, 
Bokhari, & Khan, 2010; Hafez, Hassan, Musa, Atty, & Azim, 2017; Mohammadian, 

 
 
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Fatahi, Zaeri, & Vakili, 2015; Nwosu & Maranda, 2014; Shih, Mittelman, 
Pitukcheewanont, Azen, & Monzavi, 2016). 
According to the Food and Drug Administration (FDA), The Institute of 
Medicine’s (IOM) recommended Upper Limit (UL) for chronic vitamin D intake for 
infants (children less than 1 year of age) is 25 mcg/day (1,000 IU/d), and for children 
age 1 year and older the recommended UL is 50 mcg/day (2,000 IU/d) (Institute of 
Medicine Standing Committee on the Scientific Evaluation of Dietary Reference 
Intakes, 1997). 
Despite a large amount of evidence from observational and experimental studies 
supporting the effects of vitamin D on glucose metabolism and the immune system, 
results from clinical studies remain inconsistent, which makes it impossible to 
recommend vitamin D supplementation for the treatment of T1DM. Therefore, this 
study aimed to screen for vitamin D deficiency and to examine the effects of vitamin D 
supplementation on glycemic control among children with T1DM. This is the first 
randomized controlled trial that studied the effects of vitamin D supplementation on 
glycemic control among T1DM children in the Gaza Strip, Palestine. 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

 
 
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2. Materials and Methods 
2.1 Study design 
The study design was an experimental, randomized controlled trial. 
2.2 Study setting 
The study was conducted at the endocrinology outpatients' clinic at Al-Rantisi 
Pediatric Hospital in Gaza Strip. 
2.3 Study Sample  
After getting the ethical approval from the Palestinian Ethical Committee 
(Helsinki Ethics Committee) (PHRC/HC/273/17), and the Informed Consent from 
parents of children, data were collected for 3 months, starting from October 2017 to 
January 2018. In this period, 80 children who were less than 14 years old were 
diagnosed with T1DM which was indicated through fasting blood glucose level greater 
than 126 mg/dl or HbA1c cut point of ≥6.5% (American Diabetes Association, 2010), 
and had vitamin D deficiency which indicated by its levels of less than 12 ng/ml 
(Sullivan, 2019), were recruited from endocrinology outpatients' clinic at Al-Rantisi 
Pediatric Hospital in Gaza Strip. 
 
2.4 Eligibility Criteria 
2.4.1 Criteria for children with T1DM:  
2.4.1.1 Inclusion criteria for children with T1DM: 
1- 
Children (4-14 years of age) of both gender, with a T1DM. 
2- 
Not on vitamin D supplementaition. 
2.4.1.2 Exclusion criteria for children with T1DM  
1. Age ≤ 4 or more than14 years old  
2. Patients with T2DM 
3. Children had received vitamin D supplements 
 
2.5 Sampling  
A stratified random sampling technique was applied to assign children with the 
previously mentioned criteria into two groups. The first group is the interventional 
(experimental) group that received vitamin D supplements (2000 IU/day) and the 
second group is the control group that did not receive any supplements. Both groups 

 
 
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were on their regular diet and treatment. According to previous studies and after the 
direct supervision from the treating pediatrician and endocrinologist, the best 
preparation and dosage of vitamin D was used (According to FDA the recommended 
dose for children age 1 year and older is 2,000 IU/day). The two groups were defined 
as follows: 
Group A: is the interventional group that supplemented with vitamin D tablets 
containing 2000 IU once time daily with a meal, for 3 months of intervention. 
Group B: is the control group, that did not receive any type of supplements 
during the intervention period. 
 
Concerning the laboratory investigations; vitamin D status was assessed by 
measuring the concentration of 25-hydroxyvitamin D (25(OH)D) in the children's 
serum. Levels of 25(OH)D were interpreted as deficiency (≤20 ng/ml or ≤50 nmol/L), 
insufficiency (21–29 ng/ml or 52.5-72.5 nmol/L), and sufficiency (30-100 ng/ml ng/ml 
or 75-250 nmol/L). The glycated hemoglobin levels are defined based on the control of 
diabetes, as good control (HbA1c<7.8%), moderate control (HbA1c:7.8%-9.9%), and 
poor control (HbA1c>9.9%) (Aljabri et al., 2010).  
2.6 Tools of Data Collection  
Children's health assessment structure interview sheet was used to collect data. 
It was constructed by the researchers based upon relevant literature. The questionnaire 
consisted of three parts:  
Part I: Children's socio-demographic characteristics  
This part was aimed to collect socio-demographic characteristics for both 
interventions, and control groups before the intervention such as age, gender, number 
of family members, and level of education. 
Part II: Children's current health history  
It covered the history of the discovery of diabetes, duration of diabetes, type of 
insulin, family history of diabetes, and periodic test for diabetes. This part had been 
used before the intervention for both the intervention and control groups. 
Part III: Children's laboratory investigations  
This part addressed HbA1c and vitamin D status that were investigated and 
recorded before and after the interference for both interventions, and control groups.  

 
 
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2.7 Statistical analysis  
Data was entered and statistically analyzed using SPSS (statistical package for 
social sciences) version 26 database for windows 10. Descriptive statistics were used 
to summarize the socio-demographic characteristics of subjects. Numerical data like 
25-OHD levels, and HbA1c, were presented as mean (SD) or median (IQR) based on 
their normality distribution. Categorical data were presented as frequency (percentage). 
The chi-square test was used for categorical data comparison. Analysis of quantitative 
data between two groups was done using unpaired t-test. Pearson correlation 
coefficients between continuous variables were used as a measure of association. A p-
value <0.05 was considered statistically significant. 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

 
 
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3. Results 
In our study, 83 children were found eligible. Three children did not meet the 
inclusion criteria and 80 children were randomized to the two groups (intervention and 
controls). Eighty children adhered to protocol. Data of 80 children were analyzed 
(Figure 1). 
 
 
 
 
 
 
 
 
 
 
 
Figure 1. CONSORT Flow Diagram. 
 
 
 
Assessed for eligibility  
Excluded (n=3) 
• 
Not meeting inclusion criteria (n=2) 
• 
Declined to participate (n=1) 
Analyzed (n=40) 
Adhered to protocol (n=40) 
Allocated to intervention 
 Received Vitamin D (n=40) 
Adhered to protocol (n=40) 
Allocated to control  
 Did not receive Vitamin D (n=40) 
Analyzed (n=40) 
Allocation 
Analysis 
Follow-Up 
Randomized  
Enrollment 

 
 
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Table 3. 1 General characteristic of the studied population.  
Characteristics 
 
Intervention 
group (n=40) 
Control group 
(n=40) 
P-value 
Gender 
n (%) 
 
 
 
Male 
22 (27.5) 
18 (22.5) 
0.371 
Female 
18 (22.5) 
22 (27.5) 
Educational Level 
 
 
 
Kindergarten 
6 (7.5) 
6 (7.5) 
1.000 
Elementary 
24 (30.0) 
24 (30.0) 
Intermediate 
10 (12.5) 
10 (12.5) 
First-degree relative of TIDM 
 
 
 
Yes 
7 (8.8) 
8 (10.0) 
0.775 
No 
33 (41.3) 
32 (40.0) 
Self-monitoring of blood glucose 
 
 
 
Yes 
39 (48.8) 
38 (47.5) 
0.556 
No 
1 (1.3) 
2 (2.5) 
Vitamin D categories (baseline) 
 
 
 
Vitamin D deficiency 
10 (12.5) 
25 (31.3) 
0.001 
Vitamin D insufficiency 
30 (37.5) 
12 (15.0) 
Vitamin D sufficiency 
0 (0.0) 
3 (3.8) 
Vitamin D categories (follow up 
after 3 months)  
 
 
 
Vitamin D deficiency 
1 (1.3) 
13 (16.3) 
0.001 
Vitamin D insufficiency 
2 (2.5) 
19 (23.8) 
Vitamin D sufficiency 
37 (46.3) 
8 (10.0) 
HbA1c categories (baseline)  
 
 
 
Good glycemic control 
0 (0.0) 
5 (6.3) 
0.069 
Moderate glycemic control 
12 (15.0) 
11 (13.8) 
Poor glycemic control 
28 (35.0) 
24 (30.0) 
HbA1c categories (follow up 
after 3 months)  
 
 
 
Good glycemic control 
2 (2.5) 
2 (2.5) 
0.054 
Moderate glycemic control 
18 (22.5) 
8 (10.0) 
Poor glycemic control 
20 (25.5) 
30 (37.5) 
Age (years) 
Mean ± 
SD 
8.98±3.00 
9.10±2.77 
0.256 
Duration of TDIM (years) 
3.43±2.58 
5.15±3.69 
0.030 
25-H vitamin D (Baseline) 
14.76±3.71 
12.46±4.35 
0.169 
25-H vitamin D (follow up after 
3 months) 
38.79±16.86 
14.88±4.73 
0.001 
HbA1c (Baseline) 
10.23±1.95 
9.86±2.19 
0.306 
HbA1c (follow up after 3 
months) 
9.20±1.50 
10.28±1.77 
0.324 
Mean difference of HbA1c 
levels  
-1.03±0.217 
0.423±0.217 
0.001 
 
In our study, 80 children were found eligible and were randomized into two 
groups (40 intervention and 40 controls). Table 3.1 showed the homogeneous matching 
in the general characteristics of both intervention and control groups. This is noticeable 
in the percentage of male and female participants was 27.5% & 22.5% for intervention 
group while 22.5.% & 27.5% for the control group respectively, there was no 

 
 
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statistically significant difference between the two groups P=0.371. The elementary 
level of education was 30.0% in both intervention and control groups respectively with 
no statistically significant difference between the two groups. Regarding the family 
history of TIDM, most of the study population had no first-degree relative of TIDM 
with 41.3% and 40.0% in intervention and control groups respectively P=0.775. The 
majority of the study population had compliance to self-monitoring of blood glucose 
with 48.8% for intervention and 47.5% for control groups. The mean age of the 
intervention group was (8.98±3.00 years) and the controls were (9.10±2.77 years), there 
was no statistically significant difference between the two groups P=0.256.  
In relation to vitamin D status, the mean level of vitamin D (Baseline) was 
higher in the intervention group (14.76±3.71 ng/ml) compared to controls (12.46±4.35 
ng/ml) (P=0.169). Vitamin D (Baseline) was deficient in 12.5% of the intervention 
group compared to 31.3% in the controls. While 37.5% of the intervention group had 
an insufficient level of vitamin D compared to 15.0% only among the controls 
(P=0.001). Three months of supplementation of vitamin D caused a significant rise in 
serum vitamin D levels to a sufficient range among the intervention group with a mean 
serum level of (38.79±16.86 ng/ml). Vitamin D (follow up after 3 months) was 
sufficient in 46.3% of the intervention group compared to 10.0% in the controls 
(P=0.001). The participants of the intervention and controls had poor glycemic control 
at baseline level with mean levels (10.23±1.95) and (9.86±2.19) respectively, the 
difference was not statistically significant (P> 0.05). After vitamin D supplementation 
for three months, 25.0% of the intervention group had poor glycemic control, while 
37.5% of the controls had poor glycemic control with a statistically significant 
difference (P=0.054). Moreover, the mean levels of HbA1c before vitamin D 
supplementation and after three months follow-up had decreased from 10.23±1.95 to 
9.20±1.50 among the intervention group. On the other hand, the mean levels of HbA1c 
before vitamin D supplementation and after three months follow-up had increased from 
9.86±2.19 to 10.28±1.77 among the controls.  
Furthermore, the mean difference of HbA1c in the intervention group 
was -1.03±0.217, while in the control group was 0.423±0.217, with a 
statistically significant difference detected between children in both groups 
P=0.001. 
 

 
 
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Table 3. 2 shows that there were statistically significant differences in the mean 
of glycosylated hemoglobin and vitamin D deficiency and sufficiency between 
intervention and control groups at 12 weeks (P< 0.05). Whereas, there was no 
statistically significant difference in the mean of glycosylated hemoglobin and vitamin 
D insufficiency between both groups at 12 weeks (P>0.05). 
 
Table 3. 3 Glycosylated hemoglobin levels according to vitamin D categories among 
children with T1DM and non-diabetic control groups. 
 
 
Figure 3. 1 show that 25-H vitamin D levels negatively correlated with HA1c after 
3 months follow up (r=-0.305, P=0.006). 
 
Figure 3. 1 25-H vitamin D serum levels in relation to glycemic control (%HbA1c) in 
children with T1DM group.  
Vitamin D categories 
HbA1c 
Case 
Mean±SD 
Control 
Mean±SD 
P-value 
Vitamin D deficiency 
Baseline 
10.70±0.00 
10.04±1.60 
0.030 
Follow-up 
10.60±0.00 
10.35±1.20 
Mean change 
-0.10±0.00 
0.31±1.18 
Vitamin D insufficiency 
Baseline 
14.35±1.20 
9.71±2.64 
0.394 
Follow-up 
10.30±2.55 
10.13±2.23 
Mean change 
-4.05±1.34 
0.42±1.10 
Vitamin D sufficiency 
Baseline 
9.99±1.75 
9.91±2.09 
0.016 
Follow-up 
9.10±1.46 
10.54±1.50 
Mean change 
-0.89±1.37 
0.63±1.65 
r= -0.305, P=0.006 

 
 
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4. Discussion  
The study aimed to investigate the status of vitamin D and to examine the effects 
of vitamin D supplementation on glycemic control in children with T1DM. The study 
was conducted on a homogeneous sample, who were matched in age, sex, and means 
of HbA1c, and 25(OH)D at the start point in both intervention and control groups. 
Children in the present study were  4 years of age with a mean age of 8.98±3.00 and 
9.10±2.77 years old in intervention and control groups respectively. 
It was found that 43.8% of the patients had vitamin D deficiency, 52.5% had 
insufficiency and only 3.8% were vitamin D sufficient. This high prevalence of vitamin 
D deficiency and insufficiency in patients with T1DM was previously reported in the 
Gaza strip. In the Islamic University of Gaza, Elhamalawi et al. enrolled 44 children 
with T1DM to assess their vitamin D levels and concluded that 11.4 % were vitamin D 
deficient and 45.5% were vitamin D Insufficient (Elhamalawi, 2015). 
 In the current study at the start point, mean levels of diagnostic HbA1c were 
10.23±1.95 and 9.86±2.19 in both intervention and control groups respectively and 
most of the children in both groups had vitamin D deficiency and insufficiency. While 
after 3 months HbA1c mean in the intervention group was 9.20±1.50 compared with 
10.28±1.77 in the control group. These findings were in the same line with El-Sayed et 
al. (2019) in their study on children aged above 2 years in Egypt observed that there 
was a greater incidence of T1DM with lower levels of vitamin D (El-Sayed, Abd El 
Raaouf, & Laimon, 2019). As well as in Mohammadian and Aljabri studies, a reduction 
in the mean reduction in mean HbA1C among the vitamin D deficient group was 
observed (Aljabri et al., 2010; Mohammadian et al., 2015). 
 According to the present study, although there was no statistically significant 
difference between children who received vitamin D supplementation and those who 
have not received it regarding glycemic control, the result was clinically significant. 
This can be explained as vitamin D may act directly on β cell, promoting insulin 
secretion and regulating calcium homeostasis or through a peripheral action, increasing 
the insulin sensitivity of target cells, or regulating the activation of several calcium-
dependent enzymes involved in glucose metabolism (Gabbay, Sato, Finazzo, Duarte, & 
Dib, 2012). Moreover, a recent study in Egypt concluded that supplementation of 
vitamin D for 3 months in vitamin D deficient T1DM patients revealed that better 
glycemic control was achieved (Hafez et al., 2017). 

 
 
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On the other hand, Bizzarri et al. found that vitamin D supplementation was 
ineffective in improving glycemic control in children with T1DM of recent onset, their 
study was not confirmed the protective effect of vitamin D supplementation on β cells 
function in recent-onset diabetes (Bizzarri et al., 2010).  Moreover, Walter et al. as well 
as a meta-analysis conducted by George et al. in Scotland observed no significant 
improvement in HbA1c% or fasting blood glucose in those treated with vitamin D 
supplementation compared with those who received placebo concluding that there was 
insufficient evidence of the beneficial effect of vitamin D supplementation as a means 
of improving glycemic control in children and adolescents with T1DM (George, 
Pearson, & Witham, 2012; Walter et al., 2010).  
On one hand, the lack of statistical significance might be explained by our small 
sample size, while on the other this might be explained by the higher vitamin D dose 
eventually required in this subset of the population. There is still no consensus about 
the best dose of supplementation (Holick et al., 2011).  
In this study, although most of the patients were consuming vitamin D, at the 
endpoint only 45/80 had sufficient 25OHD levels, according to the Endocrine criteria. 
Surely, lifestyle variables, as clothing, outdoor sports activities, and food choice can 
impact 25OHD levels. These variables were not investigated and this represents a 
limitation of this study. A prospective case-control double-blind study must be planned 
to see if vitamin D supplementation produces better metabolic control of T1DM in 
children. Despite the limits of this work, a 25OHD deficiency correction program 
should be considered.  
Our study was limited by number due to the high price of laboratory 
investigations, and the short duration of the study. The role of Vitamin D as an 
immunomodulator needs to be further researched in T1DM patients, preferably in a 
larger sample size and for a longer duration.  
 
 
 

 
 
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5. Conclusions 
Our study revealed that in T1DM children vitamin D deficiency coincided with 
poor glycemic control. A high prevalence of vitamin D deficiency (43.8%) and 
insufficiency (52.5%) was found among children with T1DM. The HbA1c% showed 
no statistically significant difference between children who received vitamin D 
supplementation and those who have not received it regarding glycemic control, 
whereas the results were clinically significant. 
Acknowledgment 
Funding statement 
This research received no external funding. The research was supported by the 
researchers.  
Approval 
Ethical approval was obtained from the Palestinian Ethical Committee (Helsinki 
Ethics Committee) (PHRC/HC/273/17) to carry out the study in Gaza Strip. The formal 
letter of request was obtained from the Palestinian Ministry of Health to facilitate the 
task of the researchers.  
Conflict of interest  
All the authors declare no conflict of interest. 
Author’s Contribution 
All the authors have accepted responsibility for the entire content of this 
submitted manuscript and approved submission. Heba AbdAllah Al Sarraj and Ashraf 
Jaber Shaqaliah set the study design. Heba AbdAllah Al Sarraj and Heba Mohammed 
Arafat recruited the patients, collected the samples, and supplemented the patients with 
vitamin D. Ashraf Jaber Shaqaliah, Ohood Mohammed Shamallakh, and Kholoud 
Mohammed Shamallakh performed the laboratory assessment, Ohood Mohammed 
Shamallakh, and Heba Mohammed Arafat the statistical analysis. Heba AbdAllah Al 
Sarraj wrote the original draft preparation. Heba Mohammed Arafat, Ohood 
Mohammed Shamallakh, and Kholoud Mohammed Shamallakh wrote, reviewed the 
research. All authors have read and agreed to the published version of the manuscript. 
Availability of data and materials 

 
 
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The datasets analyzed during the current study are available from the 
corresponding or first author on reasonable request. 
 
This randomized controlled trial was registered in the ClinicalTrials.gov, 
Protocol Registration and Results System (PRS) (ClinicalTrials registration number: (-
----). 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

 
 
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