新疆小儿支气管哮喘流行病学调查

对乌鲁木齐市(分工业区和居民区)、阿勒泰市、吐鲁番市0～14周岁儿童进行了哮喘的流行病学调查。调查结果:小儿哮喘总患病宰为0.52％;男性患病率高于女性;汉族患病率(0.70％)高于维吾尔族(0.35％)和哈萨克族(0.26％);哮喘发作以冬季和无明显季节性为多;发病诱因以感冒为首;多数患儿有个人过敏史和家族过敏史。对乌鲁木齐市儿童哮喘患病情况与气象因素的关系作了初步分析。     

乌海市3种主要过敏性疾病患病情况调查

目的：了解乌海市居民过敏性鼻炎、支气管哮喘、过敏性皮炎3种主要过敏性疾病的患病情况,为预防和控制过敏性疾病及卫生决策提供依据。方法：采用多阶段分层随机抽样的方法,抽取乌海市3区常住居民3 503人作为本次调查的调查对象,进行问卷调查。结果：3种主要过敏性疾病的患病率为21.50%,过敏性鼻炎、过敏性皮炎、支气管哮喘患病率分别为15.79%、3.48%、2.23%;不同年龄组过敏性鼻炎患病率差异有统计学意义（χ^2=29.46,P〈0.01）,不同职业人群支气管哮喘患病率差异有统计学意义（χ^2=4.48,P〈0.05）。结论：乌海市过敏性鼻炎患病率较高,位于3种过敏性疾病患病率的第1位,应采取积极的预防控制措施;支气管哮喘发病与接触粉尘、化学品、有害气体等生产性有毒、有害因素有关。     

960例儿童哮喘病人分析

目的 分析960例哮喘病人患病情况，以了解儿童哮喘的发病情况。方法选择在本院小儿哮喘中心建立哮喘管理档案的960例哮喘患儿，分析哮喘病人的性别、年龄、病史、好发季节、触发因素、先兆症状、个人及家族过敏史、治疗情况。结果男性发病率比女性高，3岁内发病占43．75％，发病与季节无关，占69．58％，发病诱因以呼吸道感染(可能部分为过敏性鼻炎)为首，咳嗽、打喷嚏、流涕为主要先兆症状，影响约1／4患儿身高或体重生长。结论哮喘发生与性别、年龄、呼吸道感染、过敏性疾病、亲属过敏史有密切关系。吸人疗法还需进一步推广普及。     

顺德龙江地区儿童过敏性疾病流行现状及致敏原分布

目的:统计并分析顺德龙江地区儿童过敏性疾病的流行现状及致敏原的分布情况。方法:选取2016年10月-2019年10月本院收治的各类过敏性疾病患儿540例作为研究对象,测定所有患儿血清中总免疫球蛋白E抗体(IgE)和过敏原IgE特异性抗体(SIgE),统计540例患儿过敏性疾病流行现状及致敏原的分布情况。结果:湿疹、过敏性胃肠炎、过敏性结膜炎、过敏性鼻炎、支气管哮喘、混合过敏性疾病的IgE阳性率分别为82.8%、87.5%、88.9%、89.9%、89.7%、92.0%。2岁以内儿童湿疹和过敏性胃肠炎的发病率较高,分别为84.4%、81.3%;2～4岁以过敏性结膜炎、过敏性鼻炎、支气管哮喘、混合过敏性疾病为主,分别为58.3%、50.7%、44.1%、48.0%;4岁以上以过敏性鼻炎、支气管哮喘、混合过敏性疾病为主,分别为44.9%、49.3%、42.7%。过敏原构成比例中吸入性过敏原以粉尘螨、屋尘螨为主,分别占12.0%、11.1%;食物性过敏原以牛奶和鸡蛋为主,分别占59.3%、57.0%。湿疹和过敏性胃肠炎以1种过敏原阳性占多数;过敏性结膜炎、过敏性鼻炎、支气管哮喘、混合过敏性疾病以2种过敏原阳性占多数。湿疹和过敏性胃肠炎以食物性过敏原为主,过敏性结膜炎、过敏性鼻炎、支气管哮喘、混合过敏性疾病以吸入性过敏原为主。结论:顺德龙江地区儿童过敏性疾病及致敏原分布有一定特点,应按照过敏性疾病的特点做好预防及诊疗。     

儿童及婴幼儿哮喘诊断及治疗中常见的问题

哮喘是近年来十分引入关注的全球公共健康问题,也是儿童期最常见的慢性呼吸道疾病。象哮喘这类过敏性疾病,包括过敏性哮喘、过敏性鼻炎、湿疹等,在工业化发达国家发病率居高不下,很多发达国家哮喘发病率超过10％;在我国哮喘的发病情况     

过敏性鼻炎和哮喘的联合诊断和治疗

过敏性鼻炎与哮喘均为呼吸道炎症，常在同一患者身上共存，约21％-58％的过敏性鼻炎患者伴有哮喘，而哮喘患者中伴过敏性鼻炎者约占28％～92％。Grossman更是明确提出“同一气道，同一疾病”的观点，以强调上下呼吸道疾病的整体性。现在认为，过敏性鼻炎和哮喘并非各自独立存在的疾病，已经被不同的研究者称为“过敏性鼻炎-哮喘综合征”、“联合气道疾病”、“过敏性鼻支气管炎”或“全呼吸道炎症综合征”。更多证据支持过敏性鼻炎-哮喘综合征这个新的医学诊断名称。     

内蒙古草原地区过敏相关疾病多次使用抗生素调查研究

背景　目前人们常误将过敏性鼻炎当作感冒,存在误用抗生素现象,近年来包括过敏性鼻炎在内的过敏相关疾病患病率逐年增加。而误用或滥用抗生素是造成细菌耐药的主要原因。目的　分析内蒙古草原地区3种常见过敏相关疾病过敏性鼻炎、结膜炎和哮喘多次使用抗生素的情况。方法　于2015年5-8月,采取多阶段分层抽样法,在二连浩特市、锡林浩特市、多伦县、扎鲁特旗、开鲁县和通辽市进行调查。调查其人口学资料（性别、年龄、民族、居住地等）,最近2年内抗生素多次使用情况,过敏性鼻炎、结膜炎和哮喘患病情况,家族过敏史等。结果　共发放问卷5 944份,回收有效问卷5 787份,有效回收率为97.36%。5 787例受试者中,多次使用抗生素1 079例（18.65%）,未多次使用抗生素4 708例（81.35%）;过敏性鼻炎737例（12.74%）,结膜炎512例（8.85%）,哮喘104例（1.80%）,鼻结膜炎921例（15.91%）,过敏性鼻炎伴哮喘或结膜炎伴哮喘100例（1.73%）,鼻结膜炎伴哮喘170例（2.94%）。有3种常见疾病任意一种及以上者（TCD）2 544例（43.96%）,无3种常见疾病任意一种者（NTCD）3 243例（56.04%）。男性、女性、2~17岁、18~80岁、汉族、蒙古族、其他民族、城镇、农村的TCD患者多次使用抗生素发生率高于NTCD（P<0.05）。过敏性鼻炎、结膜炎、哮喘患者多次使用抗生素发生率分别高于未患该疾病者（P<0.01）。过敏性鼻炎、结膜炎和哮喘患者多次使用抗生素发生率分别是无该种疾病者的1.53倍〔95%CI（1.33,1.76）,P<0.01〕、1.33倍〔95%CI（1.15,1.53）,P<0.01〕和2.12倍〔95%CI（1.68,2.67）,P<0.01〕。过敏性鼻炎、结膜炎、哮喘患者中,有家族过敏史者多次使用抗生素发生率高于无家族过敏史和家族过敏史不详者（P<0.01）。结论　3种常见过敏相关疾病在调查人群中患病率高,且多次使用抗生素发生率较正常人群显著增高,多次使用抗生素对有家族过敏史人群过敏性鼻炎、结膜炎和哮喘患病风险有附加作用。该资料为抗生素的规范使用管理以及过敏性疾病的防治提供了一定的数据支持。     

武汉城区部分居民支气管哮喘患病调查与危险因素分析

目的 了解武汉城区部分居民支气管哮喘的发病情况及可能的相关因素,为支气管哮喘发病的流行病学研究提供参考。方法 采用随机抽样的方法,抽取武汉城区一居委会700余户居民进行问卷调查。结果 调查样本1082人,支气管哮喘的患病人数35人,现患率3.23％。男性患病率3.59％,女性患病率2.77％。0～14岁年龄组患病率4.76％,15～24岁年龄组患病率2.10％,25～59岁年龄组患病率2.52％,60岁以上年龄组患病率7.89％。有哮喘家族史是发病的高危因素(OR=9.62),同时患有其他过敏性疾病也是发病的重要危险因素(OR=8.27)。一楼居民相对其他楼层发病率高(OR=2.81)结论 武汉城区部分居民的支气管哮喘的发病率为3.23％,其中老年人的发病率最高,儿童次之。发病的危险因素包括遗传背景、居住条件等。     

湛江地区243例哮喘儿童发病因素分析

[摘要]：目的 调查湛江市儿童哮喘的发病情况,为本地区儿童哮喘防治提供依据。方法 调查自2008年8月～2009年11月广东医学院附属医院儿科门诊收治的哮喘儿童,采用就诊病人问卷调查表的方法,由患儿家长或监护人协助完成。结果 共收集243例患儿,男童186例女童57例,男童发病率明显高于女童;56.37％哮喘患儿有过敏性鼻炎史,一、二级亲属有哮喘或过敏者占41.98％以上;诱发因素主要为呼吸道感染,其次为天气变化、运动、食物和药物过敏等;发病季节多在冬、春季。结论 湛江地区哮喘患儿患过敏性疾病如婴儿湿疹、过敏性鼻炎的患病率较高,占61.32％。过敏原检测中尘螨、花粉、海鲜等的阳性率偏高,与该地区的地理位置、气候、饮食习惯有很大关系。     

湛江地区243例哮喘儿童发病因素的分析

[摘要]：目的 调查湛江市儿童哮喘的发病情况,为本地区儿童哮喘防治提供依据。方法 调查自2008年8月～2009年11月广东医学院附属医院儿科门诊收治的哮喘儿童,采用就诊病人问卷调查表的方法,由患儿家长或监护人协助完成。结果 共收集243例患儿,男童186例女童57例,男童发病率明显高于女童;56.37％哮喘患儿有过敏性鼻炎史,一、二级亲属有哮喘或过敏者占41.98％以上;诱发因素主要为呼吸道感染,其次为天气变化、运动、食物和药物过敏等;发病季节多在冬、春季。结论 湛江地区哮喘患儿患过敏性疾病如婴儿湿疹、过敏性鼻炎的患病率较高,占61.32％。过敏原检测中尘螨、花粉、海鲜等的阳性率偏高,与该地区的地理位置、气候、饮食习惯有很大关系。     

广州市区青少年哮喘和过敏性疾病流行变化趋势调查

目的了解广州市区青少年哮喘、过敏性鼻炎、湿疹的患病率变化趋势.方法按照儿童哮喘及其他过敏性疾病的国际间对比研究（ISAAC）阶段Ⅲ方案,对广州市4个中心城区10所中学的3516名13～14岁青少年进行横断面问卷调查,并将结果与1994～1995年ISAAC阶段Ⅰ作对比.结果书面问卷中,近12个月喘息和运动后喘息症状的患病率,分别由阶段I的3.4%和17.4%上升为阶段Ⅲ的4.8%和23.4%（P〈0.01）,而医生诊断哮喘的患病率（阶段Ⅰ为3.9%,阶段Ⅲ为4.6%）在两阶段间比较差异无统计学意义.录像问卷中,阶段Ⅲ的近12个月休息时喘息和运动后喘息患病率分别为3.8%和11.3%,也高于阶段Ⅰ的2.0%和6.9%（均P〈0.01）.无感冒时有鼻炎和鼻结膜炎症状的近12个月患病率,分别由阶段Ⅰ的39.5%和8.7%上升为阶段Ⅲ的45.5%和11.1%（均P〈0.01）;同时,医生诊断为季节性花粉过敏和过敏性鼻炎的患病率,分别由阶段Ⅰ的2.9%和17.4%上升为阶段Ⅲ的4.1%和22.7%（均P〈0.05）.近12个月湿疹症状的患病率,由阶段Ⅰ的1.3%上升为阶段Ⅲ的2.2%（P〈0.01）,而医生诊断湿疹的患病率,两阶段间比较差异无统计学意义（P＞0.05）.男性哮喘、过敏性鼻炎、湿疹的近12个月症状及医生诊断患病率上升的幅度均较女性明显.结论广州市13～14岁青少年哮喘及过敏性鼻炎、湿疹患病率均较7年前高,且以男性上升明显.     

北京地区儿童呼吸道过敏性疾病与皮肤过敏原试验的调查

目的　了解北京市城区与郊区儿童呼吸道过敏性疾病的发病情况及皮肤过敏原点刺试验的情况。方法　 2 0 0 1年 10月至 2 0 0 2年 1月期间 ,采用“国际间儿童哮喘及其他过敏性疾病的对比研究”的调查方案及标准问卷 ,在北京朝阳区 (城区 )及通州区 (郊区 )按随机整群抽样法 ,共调查了 2 1所中学以 13～ 14岁为主的初一及初二年级的全部学生 70 77名 (城区 35 31名 ,郊区 35 4 6名 ) ;并在参加调查的学生中 ,再随机整群抽样 ,对城区和郊区各 10 0 0名左右的儿童进行 13种常见过敏原的皮肤点刺试验。结果　城区儿童既往喘息发病率为 12 4 %、近 12个月喘息发病率为 7 2 %、近 12个月运动后喘息发病率为 2 5 6 %、近 12个月夜间干咳发病率为 19 3% ;而郊区儿童此 4项调查结果分别为4 5 %、4 3%、12 5 %及 8 3%。城区儿童既往未感冒或着凉时即有打喷嚏、流鼻涕或鼻塞等过敏性鼻炎表现的占 4 6 1% ,近 12个月发生过的占 35 6 % ,有鼻子不适同时伴眼痒流泪的为 10 3% ;郊区学生有这些症状的比例分别是 2 1 3%、12 3%和 3 3%。 13～ 14岁城市儿童过敏性鼻炎的患病率达 8 4 %。以上各种情况患病率北京城区均明显高于郊区 (P <0 0 5 )。城区儿童 13种过敏原皮肤点刺试验阳性率均明显高于郊区儿童 (P <0     

Asthma, atopic eczema and allergic rhino-conjunctivitis in school children

International Study of Asthma and Allergies of Childhood (ISAAC) phase one study had already been completed in two age groups in 156 collaborating centers of 56 countries involving a total of 721601 children. Bangladesh did not participate earlier in this worldwide study. To determine the prevalence of asthma, allergic rhinitis and eczema in school children of Dhaka district using ISAAC protocol. A school based cross sectional study done in 2000 by using both written questionnaires (WQ) and video questionnaires (VQ). Students of class-VIII (13-14 years) filled up both the WQ and VQ and the parents of class I (6-7 years) filled up only the WQ on behalf of the students. Sixty five (6)5 primary schools and 39 high schools were randomly selected from all 19 thanas to cover equally both the urban and rural schools of the entire area of Dhaka district. A total of 6260 written questionnaires were eligible for the analysis (3029 form 6-7 years of class I and 3231 from 13-14 years of class VIII). In addition, the validated international video questionnaires were used for the older age group (3231). The symptoms of atopic diseases in the previous 12 months or ever in all children, both age groups, both sexes and in both urban and rural areas. The life time (ever) and 12-month period (recent) prevalence of three allergic conditions with 95% CI were as follows : wheezing 13.8% (12.9-14.6), 7.6% (6.9-8.2); allergic rhinitis 25.0% (23.9-26.1), 20.0% (19.1-21.1) and eczema 8.7% (CI 8.0-9.4), 6.5% (5.9-7.2). respectively. The prevalence of wheezing and other atopic features in both age groups of 6-7 years and 13-14 years showed higher features of recent wheeze in the younger children than in the older children, recent wheeze 9.1% Vs 6.1%; but the other atopic features were found lower in younger age group, recent rhinitis 16.3% Vs 23.5%, 0.001; conjunctivitis 6.4% Vs 8.3%, 0.001; recent eczema 6.0% Vs 7.1% 0.001. Male children were found to be more suffering from all types allergic conditions than their female peers: recent wheeze 9.0% Vs 5.9%, recent rhinitis 21.9% Vs 17.9%, recent allergic conjunctivitis 8.7% Vs 6.7% and recent eczema 6.8% Vs 6.2%). Though the prevalence of asthma and atopic eczema was lower than those of developed countries but still appeared to be a major health problem for our children. Allergic rhinitis was the commonest of all atopic problems in children. The younger children (6-7 years) were more likely to suffer from wheeze (asthma) but other allergic problems were more in older group of children (13-14 years). Male children were more prone to all types of allergic problems, whether wheeze or other atopic conditions, than the female peers.     

上海市郊区儿童过敏性疾病过敏原的研究

目的 分析引发上海市郊区儿童过敏性疾病过敏原的分布特点。方法 对800例上海市郊区过敏性疾病患儿（郊区病例组）、100名郊区健康儿童（郊区正常对照组）和450例上海市城区过敏性疾病患儿（城区病例组）进行过敏原皮肤点刺试验（SPT）。将郊区病例组患儿按年龄分为婴幼儿组、学龄前组和学龄组,比较各组SPT及各过敏原阳性率。结果 郊区病例组SPT阳性率（73.38%）高于郊区正常对照组（26.00%）,低于城区病例组（80.22%）,差异均有统计学意义（P<0.05）。郊区病例组患儿主要过敏原为粉尘螨和屋尘螨,阳性率分别为57.88%和59.13%。除杂草和橡胶外,郊区病例组各过敏原阳性率与其他两组比较,差异均有统计学意义（P<0.05）。各年龄组郊区过敏性疾病患儿SPT阳性率比较,差异有统计学意义（P<0.05）。结论 上海市郊区过敏性疾病患儿的主要过敏原为屋尘螨和粉尘螨;郊区过敏性疾病患儿SPT阳性率低于城区患儿,并与年龄有一定相关性。     

日本四日市小学生多种变态反应性疾病的流行病学调查

[目的]为阐明儿童变态反应性疾病漫延扩大的诱因提供流行病学调查依据。[方法]通过健康调查表，对日本四日市旧污染区楠小学校及非污染物下野小学校的学生进行有关变态反应性疾病患病情况的流行病学调查。[结果]下野小学调查对象中患过敏性鼻炎学生占23．4％，显著高于楠小学（占14．4％）（P〈0．01），而楠小学调查对象中患荨麻疹学生占6．8％，显著高于下野小学（占3．6％）（P〈0．05）。两校调查对象有既往史的父母及祖父母中，占前2位的疾病分别是花粉症和过敏性鼻炎。其中，下野小学调查对象的父亲和祖父母花粉症既往史率分别为26．2％和20．8％，显著高于楠小学（分别为20．0％和11．8％）（P〈0．05或P〈0．01）。两校调查对象的变态反应相关疾病患病率与其父母及祖父母既往史有密切的相关性（P〈0．05或P〈0．01）。[结论]遗传因素、环境因素及饮食习惯对该两所学校学生的变态反应相关疾病诱发起重要的作用。     

Prevalence and severity of symptoms of asthma, allergic rhino-conjunctivitis and atopic eczema in secondary school children in Ibadan, Nigeria

This study was part of the effort of the International Study of Asthma and Allergies in Childhood (ISAAC) Steering Committee to evaluate the epidemiology of asthma and allergic diseases around the world. Three thousand and fifty eight randomly selected children aged 13-14 years were studied, using a standard questionnaire developed and field tested by the ISAAC Steering Committee, to establish the prevalence and severity of symptoms of asthma, allergic rhinoconjunctivitis and atopic eczema. Of the 3,058 children, there were 1,659 (54.3%) females and 1,399 (45.7%) males (F:M ratio 1.2:1). The cumulative prevalence rates of wheezing, rhinitis other than common cold, and symptoms of eczema were 16.4%, 54.1% and 26.1%, respectively while within the immediate 12-month period, the rates were 10.7%, 45.2% and 22.4%, respectively. However, rhinitis associated with itchy eyes (allergic rhinoconjunctivitis) was reported by 39.2% of the school children. The prevalence of doctor-diagnosed asthma was 18.4%. Multiple logistic regression analysis showed that a higher prevalence of wheezing and rhinitis was associated with itchy eyes. The prevalence of severe symptoms of asthma, allergic rhinitis and eczema were higher when compared with a similar study in Kenya. However, the prevalence of symptoms of asthma was lower and that of allergic rhinoconjunctivitis higher in our series. There is a need for further studies to investigate the risk factors which might be responsible for the apparently different patterns in these two African countries.     

The prevalence of allergic diseases among Croatian school children according to the ISAAC Phase One questionnaire.

BACKGROUND: The prevalence of asthma and allergic diseases in children has been increasing worldwide over the past decades. The ISAAC Phase I results supplies valuable information on the worldwide variations in the prevalence of these diseases. Although ISAAC Phase I was completed in 56 countries, not all regions of Croatia were covered. Because of Croatia's high regional diversity, the aim was to explore the prevalence of asthma, allergic rhinitis/rhinoconjuctivitis, and atopic eczema symptoms in the Medimurje region in northern Croatia and compare the results with data from other regions in Croatia and other countries. MATERIAL/METHODS: The study was undertaken between January and April 2005 among 12- to 14-year-old children in 27 elementary schools. Data were collected using the standardized ISAAC written and asthma video questionnaires. RESULTS: A total of 3111 children participated in the study, with a participation rate of 94.33%. 27.6% of the children had symptoms of allergic diseases at some time in their life. Estimated lifetime (ever) prevalence of symptoms were: wheezing 11.86%, allergic rhinitis symptoms 12.21%, and atopic dermatitis symptoms 7.01%. Estimated 12-month prevalence rates were: wheezing 5.11%, allergic rhinitis symptoms 10.87%, allergic rhinoconjunctivitis 7.14%, and atopic dermatitis symptoms 5.34%. CONCLUSIONS: Compared with previous studies conducted in other Croatian regions (the city of Zagreb and a northern Adriatic region) using similar methods, the prevalence of asthma and allergic rhinitis was lower than in the northern Adriatic region but comparable with that in the city of Zagreb, and of atopic dermatitis symptoms in the same range.     

蚌埠市龙子湖区7271例社区65岁以上老年人体检结果分析

目的分析2017年龙子湖区老年人体检人群中高血压患病率及其他体检指标情况,为该区人群疾病防治和保健工作提供依据。方法收集龙子湖区7个乡镇共计7 271例65岁及以上老年人的体检数据,从性别、年龄、高血压及相关生化指标方面进行分析。结果7 271例调查对象中高血压、糖尿病的患病率分别为54.11%、21.24%,男性老年人谷氨酸氨基转移酶（ALT）、总胆固醇（TC）、三酰甘油（TG）、血清低密度脂蛋白胆固醇（LDL-C）、血清高密度脂蛋白胆固醇（HDL-C）异常率均低于女性,血清肌酐（Cr）、血尿素氮（BUN）异常率高于女性（P < 0.01）。不同年龄组老年人高血压患病率、体质量指数（BMI）、FPG、ALT、Cr、BUN、TC、TG异常率,不同BMI组老年人高血压、糖尿病患病率、FPG、ALT、AST、Cr、BUN、TC、TG、LDL-L、HDL-L异常率,不同文化程度老年人高血压患病率、BMI、AST、TC、TG、LDL-C、HDL-C异常率,差异均有统计学意义（P < 0.05~P < 0.01）。结论辖区内老年人高血压、糖尿病患病率较高,分别为54.11%和21.24%,健康状况不容乐观,建议基层医疗机构的全科医生要高度重视体检结果异常者的复查和转诊工作,同时加强针对性的健康教育,积极控制相关健康危险因素,对确诊的慢性病病人进行规范管理。     

Effect of environmental endotoxin exposure on development of pediatric asthma among Egypytian school children

Objective： The aim of this study was to assess school indoor exposure to microbial products and prevalence of asthma and allergies in rural and urban children. Methods： This study was carried on a rural and an urban school. Environmental endotoxin level was measured in multiple samples of the ambient indoor air dust collected on special aseptic filter papers from the two schools. For two hundred children history taking, clinical examination, allergen skin prick test and basic pulmonary func- tion test were preformed. Results： Environmental endotoxin levels showed significantly higher mean values （P 〈0.01 ） in rural school （3 EU/mg） as compared to the urban school （0.1 EU/mg） with （OR=5. 163; 95% CI： 0.95-28）. History of allergic symptoms was significantly more in urban than rural students （ P = 0.01 ）. Mean values of pulmonary function parameters were significantly lower values in urban students compared to rural students. Skin prick test results showed significant reactions to all tested allergens in urban children compared to rural children （ P 〈 0.05 ）. Conclusion： There is an inverse association between environmental exposure to endotoxins and susceptibility for allergic manifestations in school children.