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Background & Objective: Unnecessary pre-operative ordering of red blood cells (RBCs) in elective surgeries increases costs and waste of blood inventory. Maximum surgical blood order schedule (MSBOS) is a helpful strategy in the estimation of blood units needed for surgery and the prevention of overconsumption. In this study, an MSBOS for pediatric cardiac surgeries is designed. Methods: In this cross-sectional study, we included all pediatric patients who underwent elective cardiac surgery in Children's Medical Center in Tehran, Iran, from March 21, 2019, to September 22, 2019. Data consisted of the type of surgery and the number of blood units transfused and units cross-matched, based on which cross-match to transfusion ratio (CTR), the transfusion index (TI), and transfusion probability (T%) were calculated. Results: Overall 205 pediatric patients were included in the study. Four hundred and ten RBCs units were cross-matched, and 262 were transfused. The overall results of the CTR, T%, and TI for all the eight types of cardiac surgery were 1.56 (410/262), 76% (157/205), and 1.28 (262/205), respectively. The raw MSBOS for cardiac surgeries included ventricular septal defect, tetralogy of fallot, dextro-transposition of the great arteries, atrial septal defect, aortic coarctation, patent ductus arteriosus, pulmonary stenosis, and pacemaker insertion, which were 1.58, 1.03, 1.54, 1.66, 0.77, 0, 1.25, and 0 unit, respectively, and the figures were rounded up. Conclusion: Accurate MSBOS protocols reduce cross-match workload in laboratories, lead to the appropriate use of blood stocks with less wastage, save human and economic resources, and eventually, promote patient safety. [ABSTRACT FROM AUTHOR]

Impact of dust concentration and weather conditions – wind speed and relative humidity – on power generation of photovoltaic (PV) panels investigated experimentally in Tehran, Iran, for the period of April 10–September 22, 2018. Two Photovoltaic panels together with data-logging equipment were applied in this experiment. One panel was cleaned every day, while the other was remained unclean after 45 days. A performance ratio called "cleanness index" (CI) which is a temperature-corrected performance ratio of a soiled PV panel to that of a clean one was also used to indicate the dust deposition effect on PV panel performance. The uncertainty range of experimental results was between 5.27% and 5.55%. The results show that cleanness index had positive correlation with wind speed and negative correlations with relative humidity and dust concentration. Thus, in comparison to the clean PV panel, the output-power of the soiled panel reduced, approximately 8–12% per month. Furthermore, in order to numerically predict daily change of cleanness index (ΔCIPre), a linear regression model was developed and the outcome revealed that dust concentration had the most impact, with 21.56%. [ABSTRACT FROM AUTHOR]

Viral meningoencephalitis is one of the most important diseases that most commonly affect children. In many cases of viral meningoencephalitis, the underlying cause of the disease is not identified, raising the possibility of a variety of pathogens that are not routinely tested. Bocaviruses belong to a newly identified class of viruses that have been reported in some studies to be associated with viral encephalitis. In the present study, we investigated the prevalence of bocaviruses and other viruses in the patients suspected of having viral encephalitis and their associations with various demographic and clinical variables. Two hundred patients with suspected viral meningoencephalitis referred to Children's Medical Center were studied from 2019 to 2020. Age, sex, length of hospitalization, and course of the disease were gathered. Cerebrospinal fluid (CSF) samples were taken from the patients and subjected to biochemical examinations and PCR to identify the underlying cause. Bocaviruses were detected in none of the DNA samples extracted from the CSF specimens. The most identified organisms were mumps and enteroviruses. In 92% of cases, the underlying cause was not identified. PCR‐based identification of the underlying causes of viral meningoencephalitis in CSF specimens was not successful in most cases. Bocavirus was not found in any of the collected CSF samples. Further studies are required for drawing more accurate conclusions. [ABSTRACT FROM AUTHOR]

Introduction: Severe acute respiratory syndrome coronavirus (SARS-CoV2) has imposed catastrophic impressions on the world. After all the focused researches conducted in the COVID-19 area, many features remain obscure. We have surveyed 1,363 outpatients with suspected COVID-19 in Tehran, Iran. The analysis emphasized on characteristics of patients with positive PCR or serology of SARS-CoV-2. Methods: The nasopharyngeal swabs were tested for SARS-CoV2 PCR. Serum specimens were tested for SARS-CoV2 IgG and IgM. Clinical presentations of the patients, history of chronic diseases or drug use, contact with a possible COVID-19 patient and previous infection with SARS-COV2 were investigated. Results: Of the total 1,363 investigated patients, 22% had positive SARS-CoV-2 PCRs, 82% had positive IgG, 38% had positive IgM, and 31% had both positive IgM and IgG values. Positive serologic tests were significantly associated with a positive PCR test obtained previously in the course of the current disease (P value<0.001). IgG and IgM antibody values were significantly associated with underlying disease, cough, fever, chills, fatigue, and myalgia (all P values <0.001). Dyspnea was significantly associated with IgG levels (P value = 0.01), yet it was not associated with IgM serology (P value = 0.2). Positive serology tests were not associated with symptoms of coryza. GI symptoms were not associated with positive IgG test (P value = 0.1), yet it did show an association with positive IgM test (P value = 0.02). Cough, fever, chills, myalgia fatigue, dyspnea, and GI symptoms were all significantly associated with positive PCR (all P values <0.001), and symptoms of coryza did not show a significant relationship (P value = 0.8). Conclusion: Assessing antibody titers in outpatients is invaluable due to the epidemiological importance of investigations in mild or even asymptomatic cases. Since the number of such studies in non-hospitalized patients is not high, the current study can be used as a comparison model. [ABSTRACT FROM AUTHOR]

Background and Objectives: The human papillomavirus (HPV) is associated with more than 70% of the cervical neoplasm. The current study aims to evaluate the distribution of HPV genotypes in suspected women cytological specimens from Tehran, Iran. Materials and Methods: In the current cross-sectional study, HPV genotype prevalence was investigated in 433 subject women. DNA extraction was performed by High Pure Viral Nucleic Acid kit. A semi-automatically hybriSpot 24™ (HS24) setting was used for HPV typing and data interpreted by hybriSoft™ software according to instructions. Results: Pathologic data showed 181 (41.8%) had non-malignant lesions, 212 (49%) had inflammation and 40 (9.2%) reported LSIL in primary Pap-smear result. HPV was found in 143 (33%) specimens and the most comment high-risk and low-risk HPV types were HPV-16 and -6, respectively. Also, 62 (43%) were co-infected with multiple genotypes includes, 34 (24%) cases had co-infection with two HPV types, 17 (12%) cases had co-infection with three HPV types, 6 (4%) cases had co-infection with four HPV types and 5 (3%) cases had co-infection with five HPV types. There was statistically different domination on high-risk genotype in most of the co-infected samples (p<0.01). Conclusion: Current study indicates that the lesion pathology assessment was significantly associated with the HPV infection (p<0.01). Furthermore, the age group assessment shows that most of the HPV positive cases were 21 to 40 (p<0.01). The HPV infection prevalence in the current study was 33% and the most frequently reported high-risk and low-risk HPV types were 16 and 6, respectively. [ABSTRACT FROM AUTHOR]

Introduction: Head and neck neoplasms afflict all age groups including children. They manifest with various histological features and clinical behaviors. This study's aim was to provide data and analysis of the prevalence of head and neck neoplasms among the Iranian children and adolescents to help pathologists and clinicians make informed diagnosis and treatment decisions. Materials and Methods: This retrospective study was based on medical records of children and adolescents (=18 years) documented at a prestigious children's medical center stationed in Tehran, Iran. Cases diagnosed with head and neck tumors recorded from 2005 to 2016 were selected. Patients' age and sex, tumors' sites, and microscopic types were assessed. Data analysis was performed using descriptive statistics. Results: Of the 41,409 available pediatric patients' records documented over 12 years, 418 cases (1.01%) recorded head and neck tumors. Of these 418 cases, 15 recorded metastatic tumors (3.58%) and 403 recorded primary tumors. Of the primary tumors, 386 were found in the soft tissue (95.78%) and 17 in the bone (4.22%). The primary tumor patients' mean age was 5.46 years, including boys (59.8%) and girls (40.2%). The neck was the most common primary tumors' location (57.32%). Of all the primary tumors, 54.6% were benign neoplasms and 45.4% malignant. The commonest benign tumors were hemangioma/lymphangioma, and the most common malignancy was lymphoma. Mesenchymal neoplasms were the most common microscopic group followed by hematopoietic tumors. Conclusions: The analysis of these data indicates that the prevalence of pediatric head and neck tumors in the Iranian population is similar to other countries. [ABSTRACT FROM AUTHOR]

Introduction: Urinary tract infection (UTI) is one of the most common bacterial infections in childhood, and the increasing rate of antibiotic resistance to the commonly prescribed antimicrobial agents against it has become a major concern. The aim of this study was to determine the antibiotic resistance and genotyping of bacteria isolated from urine cultures in patients referred to the Children's Medical Center, Tehran, Iran. Methods: During the 1-year period, antimicrobial susceptibility profiles of strains isolated from patients with UTI were determined. Typing of the isolates causing nosocomial infections was performed by random amplified polymorphic DNA (RAPD) analysis, and the results were analyzed by Gelcompar II software. Results: In this study, 203 children (130 girls and 73 boys) were included. The patients' age ranged from 1 day to 16 years (IQR average=4 months to 4 years). The most frequent isolated organisms were Escherichia coli (118 isolates, 58%), followed by Klebsiella pneumoniae (30 isolates, 15%). Sixty-two strains (18 strains of E. coli, 13 strains of K. pneumoniae, 11 strains of Enterococcus faecium, and five strains of Burkholderia cepacia complex) had criteria of nosocomial infection. A high resistance rate to trimethoprim-sulfamethoxazole (69%) and cefotaxime (60%) was reported in E. coli and K. pneumoniae strains, respectively. Pseudomonas aeruginosa strains showed high sensitivity to amikacin (100%). All E. faecium strains were susceptible to trimethoprim-sulfamethoxazole (100%), and 23% of the strains were resistant to vancomycin. The analysis of RAPD-typing revealed the presence of three clusters in E. coli, two clusters in E. faecium, and one clone in K. pneumoniae. Besides, four out of five isolates of B. cepacia complex had more than 90% genetic similarity. Conclusion: The most frequent isolated pathogen was E. coli, and an increasing rate of antibiotic resistance to the commonly prescribed antimicrobial agents such as trimethoprim/sulfamethoxazole and cephalosporins was observed. Moreover, the results of this study showed the presence of clones with ≥ 80% similarity in E. coli, K. pneumoniae, E. faecium, and B. cepacia complex isolates; therefore, the transmission of nosocomial infections from one patient to another or one ward to another is probable. [ABSTRACT FROM AUTHOR]

Background and Objective: Attention-deficit hyperactivity disorder (ADHD) is known as the most common neurological disorder in childhood. Failure to timely diagnose ADHD can lead to harmful effects for the individual and the family. The relationship between this disorder and the addiction to video games has been reported in children. Therefore, this study aimed to investigate the degree of addiction to video games in Iranian children with ADHD, compared with normal children. Materials and Methods: In this applied research, 99 children with ADHD referring to Imam Hossein Hospital and 99 normal children in elementary schools of Tehran (control group) were recruited. Data were collected using Conner's Scale and Young's Internet Addiction Test (video games). The data were analyzed using SPSS (version 22). Results: In this study, 11% of the children with ADHD and 4% of the normal children had addiction to video games. This difference was significant between the two groups (P < 0.05). Moreover, 58% of the children with ADHD and 27% of the normal children were exposed to video games. This difference was also significant between the two groups (P < 0.05). Conclusion: The results showed that the frequency and prevalence of addiction to video games were higher in children with ADHD than in normal children. Therefore, it can be concluded that timely diagnosis of this disorder leads to better treatment. [ABSTRACT FROM AUTHOR]

aimeh Naserzadeh,1 Reihaneh Hosseinpour Sadeghi,2 Mohammad Taghi Haghi Ashtiani,3 Abbas Bahador,4 Mohammad Reza Abdosalehi,1 Maryam Rahmani,5 Babak Pourakbari21Department of Infectious Diseases, Pediatrics Center of Excellence, Children's Medical Center, Tehran University of Medical Sciences, Tehran, Iran; 2Pediatric Infectious Disease Research Center, Tehran University of Medical Science, Tehran, Iran; 3Department of Pathology, Pediatrics Center of Excellence, Children's Medical Center, Tehran University of Medical Sciences, Tehran, Iran; 4Department of Microbiology, Tehran University of Medical Sciences, Tehran, Iran; 5Pediatrics Center of Excellence, Children's Medical Center, Tehran University of Medical Sciences, Tehran, IranCorrespondence: Babak PourakbariPediatric Infectious Disease Research Center, Children Medical Center Hospital, Tehran University of Medical Sciences, 62 Gharib Street, Keshavarz Blvd, Tehran, IranTel +98 21 6642 8996Fax +98 21 6642 8996Email pourakbari@tums.ac.ir Background and aim: Hospital-acquired infection (HAI) is a major problem worldwide. Understanding patterns of bacterial etiology and antibiotic susceptibility is vital to combating HAI. Besides, typing of isolates is important to establish the intra-hospital surveillance of resistant clones. In this study, we aimed to evaluate antibiotic resistance and genotyping of a number of gram-negative bacteria (GNB) causing HAI in patients who were referred to Children's Medical Center. Methods: During the 6-month period, antimicrobial susceptibility profiles of GNB isolates recovered from patients in Children's Medical Center were determined. Typing of common GNB was performed by random amplified polymorphic DNA (RAPD) analysis and the results were analyzed by Gelcompar II software. Results: In total, 142 (1.1%) gram-negative bacterial strains were isolated, among which 59.2% were from males. The most organisms were isolated from blood (63%) followed by wounds (13.7%). The greatest proportion of strains came from intensive care units (51%). Low sensitivity of Acinetobacter baumannii to common antibiotics and high resistance of Enterobacter spp. To cefotaxime (100%) were reported. The most efficient antibiotics for Escherichia coli strains were amikacin (84%) and gentamycin (81%). However, just 12.5% of Serratia marcescens strains were resistant to trimethoprim-sulfamethoxazole. The analysis of RAPD-typing revealed the presence of one clone in A. baumannii and E. coli and two clones in Klebsiella pneumoniae, whereas the trend varied completely in Pseudomonas aeruginosa strains and Enterobacter spp. Conclusion: The results of this study showed a possibility of an outbreak in the Children's Medical Center. Since there is a possibility of transmission of an infection from one patient to another, high attention should be paid to the basic methods of preventing infection. [ABSTRACT FROM AUTHOR]

Background and Objectives: Infection with parvovirus may induce spontaneous abortion, non- immune hydrops fetalis, and intrauterine death in full term infants. The aim of this study was to determine the frequency of parvovirus B19 in paraffin-embedded formalin fixed placental tissues in lost fetuses by PCR method and comparison with its frequency in healthy full term neonates as controls. Materials and Methods: In a case control study, thirty-one formalin fixed paraffin embedded placental tissue from autopsies related to fetal losses and also the same number of control cases were collected and the PCR for internal control and target sequence were performed. Results: Thirty-one subjects and 31 controls were enrolled and three out of 31 cases were positive for parvovirus (9.7%) using PCR. Hydropic changes were noted in two of positive cases for parvovirus. Conclusion: Parvovirus B19 infection during pregnancy may cause red precursor cells damage resulting in anemia and congestive heart failure. We suggest that studies with greater sample sizes are carried out to determine the frequency and management of parvovirus B19 infection because of timely diagnosis and transfusion of severe hydropic fetuses can reduce the risk of fetal death. [ABSTRACT FROM AUTHOR]

Introduction: This research aimed to compare medical and psychological interventions to improve chronic insomnia among adult women who sought advice from a sleep clinic in the city of Tehran. Method: The study population included all of the clients in a sleep clinic in the city of Tehran suffering from chronic insomnia. The sample for this study included 26 clients, who were randomly divided into two groups with 13 clients in each group. Psychological intervention group subjects were given instructions for progressive muscle relaxation, guided imagery, relaxing music, and sleep hygiene in 4 sessions. Subjects in medical intervention group used hypnotic drugs in 4 weeks. All participants were examined after 4 weeks. The tools for obtaining information consisted of Pittsburgh Sleep Quality Index, Insomnia Severity Index, Epworth Sleepiness Scale, Berlin Questionnaire for Sleep Apnea, and Beck Depression Inventory. Results: The analysis of data showed that both psychological and medical interventions could improve sleep quality and insomnia. Comparison between the two kinds of interventions showed that psychological interventions are more effective than medical intervention. Conclusion: According to the results, we may suggest that psychological interventions are a more proper remedy for insomnia. [ABSTRACT FROM AUTHOR]

There are increasing reports of emergence of multiple drug resistant (MDR) Acinetobacter spp in the world; however there are a few reports in our country. 145 A. baumannii isolates from distinct wards and Children's Medical Center (CMC) in Tehran were studied in order to find the profile of antibiotic resistance among them. 40.6% (59/145) of A. baumannii isolates were identified as MDR. Overall susceptibility rates to cotrimoxazole, chloramphenicole and ciprofloxacin were 23.4%, 16.9% and 20.1%, respectively. Frequency susceptibility rates to amikacin, kanamycin, gentamycin and tobramycin decreased gradually from 81.2%, 50%, 50% and 62.5% in 2002 to 25%, 15.6%, 28.1% and 25% in 2007 respectively. Overall susceptibility rates to cephalosporines cephalotin, ceftazidime, cefteriaxon, ceftizoxime and cefixime were 9.3%, 14.7%, 16.2%, 15.9% and 18%, respectively. Susceptibility to carbapenems was assessed only in 2007. The susceptibility rates of Imipenem and meropenem were shown to be 50% and 46.8%, respectively. Our data indicates that MDR A. baumannii strains are spreading and carbapenem resistance is becoming more common in Iran. Our findings also highlight the importance of clinicians' access to updated susceptibility data regarding A. baumannii in developing countries such as Iran. [ABSTRACT FROM AUTHOR]

Background: Menopause is a step of a woman's life when hormonal changes cause menstruation to stop permanently. Menopausal symptoms can affect women's health and differ between different races and societies. Objective: The aim of this study was to survey the symptoms associated with menopause among Iranian women living in Tehran, Iran. Materials and Methods: In this cross sectional study which has been done between 2004 and 2005, women aged equal or more than 35 years old living in districts of Tehran were selected by multistage randomized cluster sampling. For each woman a questionnaire was completed. The data gained from each questionnaire was analyzed by using SPSS version 13. Results: At time of study, 2462 women were naturally menopause. The mean age of natural menopause onset was 47.71 (SE=0.11) years. In 52.9% of cases, the onset of menopause was sudden. The symptoms associated with menopause were night sweats (61.2%), joint and muscle pain (59.9%), hot flashes (53.1%), fatigue (45.6%), decreased libido (33.9%), insomnia (33.7%), weight gain (30.1%), forgetfulness (24.9%) and urinary symptoms (17.4%). Conclusion: This study showed that night sweats, joint and muscle pain and hot flashes are the most common symptoms associated with menopause. [ABSTRACT FROM AUTHOR]

Modeling fate of nitrogen in unsaturated and saturated zone is a complex process, which requires detailed geochemical data. Complexities of the process as well as data insufficiencies are two major issues, which make quantitative assessment of the problem more complicated. In this work, a lumped-parameter model (LPM) is proposed that has been evaluated for a data-limited case to study temporal and steady-state behavior of Nitrate and Ammonium in unsaturated zone. The concentration of components in the model are assumed as the depth-averaged concentrations, and dispersive fluxes have been neglected. The case study area is Tehran City aquifer, which is highly contaminated by domestic wastewater discharge into the groundwater. Three sources for Nitrogen contamination have been studied, namely domestic wastewater, park/recreational applications, and wet deposition. Results show that Nitrate production in the first few meters (<5 m) is quite large. To compare the model results with the measurements, error estimation analysis based on Vornoi map has been fulfilled. Finally, it is shown that there is a fairly good correlation coefficient between simulation and measurements, which approves the validity of the LPM. [ABSTRACT FROM AUTHOR]

Objective: To investigate the concept of ‘Non-affective Acute Remitting Psychosis’ (NARP) in a group of patients with first episode psychosis in Iran. Method: This is a 24-month follow-up study of 54 patients with first-episode psychosis admitted consecutively to a psychiatric hospital in Tehran, Iran. At the end of follow-up, consensus judgments were made on fulfillment of the NARP criteria as well as illness course and treatment. NARP was defined as a psychotic illness with acute onset (developed within 1 week), short duration (remission within 6 months), and the absence of prominent mood symptoms. Results: Of 49 patients who completed the follow-up, 15 (30.6%) had NARP, accounting for 60% of non-affective psychoses. Ten patients with NARP remained relapse free, four had a very short-lived relapse, and only one developed a chronic illness. Throughout the follow-up, patients with NARP received fewer months of treatment than did patients with other non-affective psychoses. Conclusion: The high proportion of NARP among patients with first episode psychosis, and the favorable course is in keeping with previous studies in developing countries. [ABSTRACT FROM AUTHOR]

BACKGROUND: Haemoglobinopathies are a group of inherited disorders of haemoglobin synthesis. Their frequency varies considerably with geographic location and ethnic group. AIMS: To establish the prevalence of haemoglobinopathies in a mainly healthy Iranian population. METHODS: All files of the haematology unit of the Boghrat laboratory over a period of 10 years (1998–2007) were analysed in relation to the age, sex, full blood count, haemoglobin electrophoresis results, high performance liquid chromatography (HPLC) findings, and iron profile of healthy subjects referred for consultation before marriage. Other tests were performed if indicated. RESULTS: There were 34 030 files; 13 432 (39.5%) were for men, and 20 567 (60.4%) for women. 0.74% of subjects (255) showed a haemoglobinopathy. The distribution of variant haemoglobins in these 255 subjects was: Hb D 75.67% (193 cases), Hb S 4.7%, Hb E 3.13%, Hb O-Arab 1.96% and Hb Lepore 0.39%. A fast haemoglobin was found in 4.71% of subjects. Of the subjects tested, 13.2% (4478) had β-thalassaemia minor, 0.2% (52) β-thalassaemia intermedia and 0.1% (30) β-thalassaemia major. CONCLUSIONS: In comparison with other parts of world, there is a different pattern of haemoglobinopathy with a high prevalence of Hb D, which appears to be Hb D Iran. [ABSTRACT FROM AUTHOR]

Vitamin D is important for calcium absorption and skeletal growth. Vitamin D insufficiency (VDI) is a prevalent health problem in children. A study was performed to determine the prevalence of VDI in healthy children living in Tehran, Iran. In a cross-sectional study, 963 students (424 boys and 539 girls) aged 7–18 years were selected by random sampling. Serum 25-hydroxyvitamin D (25-OHD), calcium, alkaline phosphatase and phosphorus were measured. VDI was defined as serum 25-OHD 20 ng/ml. Prevalence of VDI was 53.6% in girls and 11.3% in boys. VDI in female students was about five times more common than males (p 0.000001). VDI in children and adolescent girls is a health problem not only for these age-groups but also for the next generation to come. Encouraging girls to have more sun exposure, fortification of foods and prescription of supplemental vitamin D are recommended. [ABSTRACT FROM AUTHOR]

Background: Improvement of the quality of life of people with developmental disorders and their full integration within society requires comprehensive mental, intellectual, and physical rehabilitation. To achieve a favorable outcome, rehabilitation should be delivered in a continuous manner and with small attrition. Research in this area is scarce. Objectives: The current study aimed to determine the incidence of dropout from rehabilitation and its associated factors in children with developmental disorders. Methods: In this prospective study, we recruited 225 children with developmental disorders and their parent (s) seeking rehabilitation services for the first time. They attended different centers in all regions of Tehran during 2016 - 2017. We completed a checklist using semi-structured interviews. The follow-up was performed every three months for at least six months to record the dropout from rehabilitation and the associated factors. Data analysis included the chi-square test and logistic regression. Results: The dropout rate was found to be 10.9% within three months and reached a total of 19.3% in six months. It was significantly associated with the following factors after eliminating confounding effects: (1) poor family satisfaction with the centers in three-month analysis (OR = 10.76; CI: 2.764 - 41.906, P = 0.001) and after six months (OR = 4.51; CI: 1.30 - 15.67, P < 0.02); (2) the type of service sectors (public and charity vs. private) (OR = 7.12; CI: 2.12 - 23.93, P = 0.002); (3) moderate severity of the developmental disorder in three-month analysis (OR = 4.55; CI: 1.24 - 16.78, P < 0.03); (4) child’s perceived “lack of cooperation” in attending rehabilitation sessions in six months (OR = 6.79; CI: 1.42 - 32.53, P < 0.02); and (5) the type of developmental disability (specific learning disorder vs. others) in six months (OR = 6.68; CI: 2.85 - 15.65, P < 0.001). In the open questions, the high cost of services was stated as the most important reason for dropout. Conclusions: Our findings indicate that dropout was associated with family dissatisfaction with the low quality of services, mainly in the public and charity centers. Children with disabilities of moderate severity were most likely to drop out from rehabilitation. Specific learning disorders seem to be the most challenging type of disability that leads to the highest dropout rates. The findings provide opportunities for further research in this area and to gain more information to render rehabilitation services more efficiently. [ABSTRACT FROM AUTHOR]

• Developed methods for GWW estimation by pumping wells are reviewed. • RPWN an adopted method for Iran's aquifers to estimate GWW is presented and modified. • Modified RPWN adopt a few wells and keeps an acceptable level of accuracy in estimation of GWW. • Modified RPWN is a robust and consistent tool for aquifers with dense pumping wells. • Sensitivity and regression analysis are done to find important explanatory variables on GWW. In this study a review of the developed methods to estimate groundwater withdrawal (GWW) from aquifers by pumping wells is provided. Then, a method adopted by Iran's Basic Studies Bureau of Water Resources Management Company for estimation of GWW through 536 aquifers across Iran is presented and modified. This so-called "representative pumping wells network" (RPWN) approach is a combination of statistical and rate-and-time methods which has been implemented for all aquifers in Iran since 2007. The RPWN approach is based on the overlaying of 10 important features in a GIS environment and classified in a number of zones in which their withdrawals are statistically different. The representative pumping wells in each zone are sampled for RPWN based on a multi-objective optimization. Three aquifers of Tehran, Arak, and Qazvin in Iran are selected as real cases studies to demonstrate the efficiency of the modified RPWN approach. Metered pumpage of the all active wells obtained from the last official inventory in 2007 is considered as true GWW values to evaluate the current and modified RPWNs. Based on modified approach, 50 representative pumping wells (RPWs) are selected for each aquifer of Tehran, Arak, and Qazvin, respectively 58%, 11%, and 50% less than number of wells considered in the current RPWN. Whereas the computational errors of GWW by the current RPWN are between 19.9% and 26.2%, the modified RPWN shows much smaller errors in the range of 0.2% to 1.41%. Moreover, the modified RPWN reduces the cost of data compilation to 10.6% to 58.0% of the current RPWN. The results of this study demonstrate that the modified RPWN approach is a robust, efficient, effective and consistent tool and particularly suited to the aquifers that pumping wells provides a dense observation network in which data compilation of GWW impose a great deal of financial burden. [ABSTRACT FROM AUTHOR]