Levels of Selected Microelements in Premature Ovarian Insufficiency
Conditions: Premature Ovarian Failure
Sponsor: Cengiz Gokcek Women's and Children's Hospital

Full study protocol and statistical 
analysis plan 
Official Title of the study: 
Levels of selected microelements in premature ovarian insufficiency 
 
Date of the document: 
January 2021. 
Contents: 
1. Participant Flow 
2. Baseline Characteristics 
3. Outcome Measures 
4.Endpoints of the study 
5.Limitations and Strengths 
6. Certain Agreements 
7. Results Point of Contact  
 
1. Participant Flow 
Recruitment Details 
This will be an observational prospective cohort study conducted at Obstetrics and 
Gynecology Department of Cengiz Gokcek Obstetrics and Children's Hospital between 
January 2020 and June 2021. The authors will be recruited 50 subjects with idiopathic POI, 
and 50 healthy patients were selected for the control group. All patients will be given their 
oral and written informed consent before their inclusion in the study. The protocol was 
approved by the Ethics Committee for Clinical Research of Gaziantep University (Reference 
number: 2020/362). The study strictly will be adhered to the principles of the Declaration of 
Helsinki.  
Pre‐assignment Details 
The authors first will be assessed the recruited people to ensure meeting the inclusion and 
exclusion criteria. The inclusion criteria will be made according to the official documents. 
Arm/Group Information * 
 
There are two groups in the study. 

 
Arm/Group Title * 
 
Premature ovarian insufficiency group 
Control group 
2. Baseline Characteristics 
In order for the expectation that a medium effect size (d = 0.60) would occur between the 
physiological parameters of the POI group and the control group was statistically significant, 
the required minimum number in each group was determined as 45 (α=0,05; 1-β=0,80). It was 
decided to include the same number of participants of control groups to balance the POI and 
control groups. Power analysis was performed by using G power package version 3.9.1. 
Kolmogorov Smirnov and Shapiro Wilk tests will be used to test the normal distribution of 
data. For comparing groups (POI/control) the student t-test will be used for variables that have 
a normal distribution, and the Mann Whitney U test will be used for variables that have not a 
normal distribution. The ROC analysis will be applied for the determination of cut-off point 
for variables. Moreover, Spearman correlation test will be used for the relationship of between 
variables. SPSS for Windows 22.0 and Medcalc programs will be used for statistical analysis. 
p<0.05 will be accepted as statistical significance.   
 
3. Outcome Measures 
 
Primary Outcome Measures: Lead (Pb), Cadmium (Cd), Gadolinium (Gd), Arsenic (As), 
Mercury (Hg), Cobalt (Co), Vanadium (V), Titanium (Ti), Sulfur (S), Chromium (Cr), Silver 
(Ag), Molybdenum (Mo), Boron (B), Lithium (Li), and Nickel (Ni) concentrations  
 
4. Endpoints of the study:  
The primary outcome in these analyses will compare Lead (Pb), Cadmium (Cd), Gadolinium 
(Gd), Arsenic (As), Mercury (Hg), Cobalt (Co), Vanadium (V), Titanium (Ti), Sulfur (S), 
Chromium (Cr), Silver (Ag), Molybdenum (Mo), Boron (B), Lithium (Li), and Nickel (Ni) 
levels in the idiopathic POI group and control group. 
 
5.Limitations and strengths: 
There will strengths of this study. The women participating in the study had idiopathic POI 
and had not received treatment. 
6. Certain Agreements 
 

The authors declare that they have no conflict of interest. 
7. Results Point of Contact 
Corresponding Author: Ali Ovayolu, Department of Obstetrics and Gynecology, Cengiz 
Gokcek Women's and Children's Hospital, Gaziantep, Turkey, drovayolu@yahoo.com 
Address: Osmangazi Mahallesi, Cengiz Gokcek Kadın Hastaliklari ve Dogum Hastanesi, 
27010 Gaziantep, Turkey 
GSM: +90 (532) 640 40 60 
Tel.: +90.342 360 08 88 
Fax: +90.342 360 02 90