the internet , so - called information superhighway , is an accessible medium for medical information transfer , which makes the world wide web ( www ) component of internet a very powerful vehicle for providing educational materials to patients . the www contains about 800 million publicly available pages , and 3% are health - related web sites ( 1 ) . in korea , as of december 2002 , 26 million people had access to the internet and proportion of netizen ( term standing for those using internet frequently ) is ranked the third in the world ( 2 ) . some studies have reported that education programs for asthma patients improve medication compliance , decrease emergency department visits and hospitalizations , and promote the quality of life ( 3 - 5 ) . in addition , formal asthma education programs have been shown to be cost - effective ( 6 ) . it was also reported in korea that education for asthma patients was important and effective to teach correct use of metered dose inhaler and improve the quality of life ( 7 , 8) . computer - based educational programs delivered over the internet can overcome some of these limitations . indeed , many web sites for the education of asthma patients are now available on the internet ( 10 ) . however it is still debatable that these web sites provide really useful and authoritative information for asthma patients . in other medical fields , several investigators have already tried to evaluate the type , contents , and quality of medical information available on the korean internet ( 11 - 17 ) . but until now , there have been few studies of asthma - related information on the internet . the objective of this study was to assess the quality and contents of asthma - related information on the korean internet as an educational material for patients . a single key word , ' asthma ' , was entered into the most commonly utilized www search engines in korea . ' haesu ' , a traditional term for asthma - like symptoms used by general koreans , or ' hyochun ' , the corresponding orient medical term for asthma , was not used as a key word because of its vagueness . the search engines we utilized were yahoo korea ( www.yahoo.co.kr ) , empas ( www.empas.com ) , naver ( www.naver.com ) , and daum ( www.daum.net ) . these four engines rendered the results of each inquiry as a list of web site addresses , or universal resources locators ( urls ) . web sites without transparency of authorship or without comprehensive contents comprised of definition , pathophysiology , management , and advices on the prevention of asthma were excluded in the analysis . the authorship , informational value as an educational material , and informational justifiability ( defined below ) were independently evaluated by two hand physicians according to the methods described by stoo et al . ( 18 ) . when the subjective characterization of the authorship or the nature of content differed between two evaluators , a third evaluator cast the deciding vote . the authorship of each web site was assigned to one of four categories : western physician indicates a western medical doctor or doctors who were in practice or affiliated with a university ; oriental physician indicates an author or authors who were practitioners of traditional orient medicine ; commercial indicates an author or authors who were marketing medications or devices for asthma ; others indicates individuals or organizations not belonging to any of the previous categories . ( 10 ) was used to assess the value of asthma - related information as an educational material . table 1 listed these concepts . to satisfy each concept , several ideas as detailed in the ' national asthma education and prevention program ( naep ) expert panel report 2 ' ( 19 ) basic asthma pathophysiology : web sites should contain four or more of the following five ideas : chronic allergic inflammation , airway hyperreactivity , reversible airway obstruction , trilogy of symptoms ( dyspnea , cough , and wheezing ) , and the likelihood of persistent airway limitation if left untreated . triggers of asthma attacks : web sites should contain four or more of the following five ideas : allergen , air pollution and smoking , harmful medications , co - morbid conditions , and hazardous foods potentially worsening symptoms of asthma . avoidance of asthma triggers : web sites should contain four or more of the following five ideas : measures to control environment , avoidance of harmful medications or foods , treatment or prevention of co - morbid conditions , cessation of smoking , and practical methods of safe exercise . mechanism of action of medication for asthma : web sites should describe the differences between long - term - control medications and quick - relief medications , and provide details of mechanisms and complications . importance of using anti - inflammatory medication : web sites should emphasize clinical effects of anti - inflammatory therapy which include reduction in severity of symptoms , improvement in peak expiratory flow , and probable prevention of airway remodeling . importance of availability of rescue medication : web sites should teach patients to use short acting inhaled beta-2 agonist when dyspnea is aggravated , but on the other hand , warn that too great a reliance on the rescue medication is potentially harmful . self - assessment of respiratory status : web sites should emphasize self - assessment measures , such as , forced expiratory volume in 1 second ( fev1 ) or peak expiratory flow rate ( pefr ) , to allow patients to recognize a worsening of their asthma symptoms at an earlier stage . necessity of an action plan depending on respiratory status : web sites should introduce practical guidelines according to the results of self - assessment , such as , " management of asthma exacerbations : home treatment " as described by the naep expert panel report 2 ( 19 ) . if web sites contained original concepts not included in the naep expert panel report 2 , these concepts were regarded as unreliable and further evaluated using the health on the net code of conduct ( hon code ) principles ( 20 ) . these principles were proposed by the health on the net ( hon ) foundation , one of the groups that have developed generic rating tools in an attempt to objectively evaluate medical information on the www ( 21 ) . the fifth one of eight principles was used to assess informational justifiability . in brief , the criteria centered on claims relating to the benefits / performance of a specific management , commercial product or services and the support of such claims by balanced evidence and clear references to source information , and where possible , the provision of specific html links to such information . the mann - whitney u test were applied using the spss version 8.0 ( chicago , u.s.a . ) to evaluate the statistical difference among the data . after excluding duplications , 76 web sites with a unique url were identified . however among them , 32 web sites with transparency of authorship and comprehensive contents were included in our analysis and categorized with respect to authorship as follows : 8 as western physician ; 17 as oriental physician ; 4 as commercial ; and 3 as others ( table 2 ) . authors of the others sites were a pharmacist and two laymen ( family members of asthma patient ) . the mean number of core asthma educational concepts of the whole web sites was 2.7 out of 8 , and the median was 2 ( range , 0 to 7 concepts ) . there was no significant difference between the mean number of the whole web sites and that of each group ( table 3 ) . compared to the western physician sites , only the mean number of the commercial sites was significantly lower ( p<0.05 ) . one of the western physician sites , two of the commercial sites , and all of the oriental physician and others sites contained unreliable information based on the traditional concept of orient medicine or author 's personal experiences ( table 5 ) . however these web sites failed to satisfy our criteria of justifiability , that is , lacked balanced evidences , clear references to source information or specific links . only one of the oriental physician sites provided references to support its information , thus being regarded as justifiable . the greater part of unreliable information was related to treatment of asthma , for example , unique herbal medications , taping methods , placenta treatment , and fluctuation treatment ( table 6 ) . in this study we evaluated asthma - related information on the korean internet using the core asthma educational concept proposed by croft and peterson ( 10 ) and the health on the net code of conduct ( hon code ) principles proposed by the hon foundation ( 20 ) . the mean number of core asthma educational concepts on the whole web sites was 2.7 out of 8 . however only one site satisfied our criteria of justifiability . from these data we concluded that asthma - related information currently available on the korean internet is highly variable in quality and fails to meet the information needs of patients as an educational material . using same concepts as us , croft and peterson ( 10 ) evaluated 145 sites on the www containing asthma educational material and found that the mean number of core asthma educational concepts included was 4.9 . one of the reason explaining the difference between two studies was that over half of the web sites included in this study were categorized as oriental physician . in a previous report by kim et al . using a key word , ' stroke ' , 71.4% of the web sites identified on the korean internet were based on traditional oriental medicine ( 17 ) . for some concepts , which included basic pathophysiology of asthma , triggers of asthmatic attacks , and necessity of avoidance of triggers , the oriental physician sites showed a tendency to share common views of western medicine ( table 4 ) . however with respect to treatment of asthma , their approach was different from western medicine . in addition , several sites introduced quite unique forms of management , such as , ' fluctuation treatment ' or ' placenta treatment ' . therefore the oriental physician sites contained fewer core asthma educational concepts based on western medicine . confining discussion to the western physician sites , the mean number of core asthma educational concepts was 3.5 , which was still fewer than the result of croft and peterson ( 10 ) . the plausible explanation was that only a few western physician sites contained the last four concepts concerning medication and self - assessment . for effective management of asthma , knowing the importance of anti - inflammatory medication , understanding the potential harm of an excessive reliance on rescue medication , periodic self - assessment , and adjusting the level of medication according to results of self - assessment are needed ( 19 ) . in this respect , to be qualified as a good educational material , web sites on the korean internet containing asthma - related information should include information upon medication of asthma , measures of self - assessment , and action plan depending on respiratory status . surprisingly , though statistically insignificant , the mean number of core asthma educational concepts included on the others sites was higher than the western physician sites ( 5.0 vs. 3.5 ) . however information on the others sites was just a mixed collection of contents obtained from other web sites . in addition , the bulletin board system ( bbs ) of the others sites fully consisted of non - supervised recants of personal experiences . even though such information was often partly correct , its disorganized presentation is likely to confuse and mislead information - seekers , especially non - professionals . accordingly there is urgent necessity for the principles to guide development and posting of web site contents and ensure site visitors ' or patents ' right to confidentiality like " guidelines for medical and health information sites on the internet " proposed by the american medical association ( 22 ) . originally we focused on a single keyword , ' asthma ' , because we believed that it would be a popular and easy choice of those searching for asthma - related information on the internet . however , as berland et al . reported , only 20% of the search results led to relevant content when simple search term , such as ' depression ' or ' obesity ' , was entered into search engines ( 23 ) . if we had chosen combinations of several words as key words , we would have identified more web sites containing comprehensive information . the other limitation was that the core asthma educational concepts we used to assess information of web sites on the korean internet was totally based on western medicine . in korea traditional orient medicine frequently takes an alternative role to western medicine . it was quite beyond the scope of our study to evaluate whether treatments based on orient medicine work or not . however well - balanced assessment of asthma - related information on the internet would have been possible if we had developed a new evaluation principle reflecting the situation peculiar to korea . the internet has the potential to be a powerful information resources , which could fully meet a patient 's health information needs . ideally , patients would be able to learn much of what they need to know from high - quality web sites , and thus the time that they spend with their physicians could be used more efficiently . however , this requires that web sites present well - organized and accurate information in a comprehensive manner . research is needed to determine how a patient 's use of internet facilities , complements or complicates patient - physician communication and how patients and health professionals can make better use of this resource .
despite the substantial amount of asthma - related information available on the internet , little is known about the quality of such information . 
 we assessed asthma - related information on the korean internet intended as an educational material for asthma patients . by entering the key word , ' asthma ' , into 4 popular search engines , 
 32 web sites were identified and categorized with respect to authorship . 
 the core asthma educational concepts and health on the net code of conduct principles were used to evaluate informational value and justifiability of unreliable information . 
 eight of 32 web sites were categorized as western physician , seventeen as oriental physician , four as commercial , and three as others . 
 the mean number of core asthma educational concepts on the whole web sites was 2.7 out of 8 . by type of authorship , 1.7 on the commercial sites , 2.1 on the oriental physician sites , 3.5 on the western physician sites , and 5.0 on the others sites in decreasing order . 
 one of the western physician sites , two of the commercial sites , and all of the oriental physician and others sites contained unreliable information . 
 however all of them except one site failed to satisfy our criteria of justifiability . 
 asthma - related information currently available on the korean internet is highly variable in quality and lacks core asthma educational concepts and justifiability .