Methods

 

Study Design

    This study is a systematic review of observational studies, using articles from online databases. Based on the articles and on a qualitative study we will be able to assess the proportion of asthma control in children.

 

Study participants

    The target population of our study are all the observational studies on children (below the age of 18 years old) resident in Europe, who suffer from asthma.

 

 

Data Collecting Methods

 

    Data Search

    The Data Search Methods which will be used include three stages, defined by the students, following a logical stream.

    A preliminary research was conducted by three individuals separately, in order to collect the key-words referring to the articles which answered to the research question established. These were the findings: “Asthma”; “Children”; “Europe”;”Control”.

    In a second stage, a query for each chosen database was necessary, so the class was divided in three groups: two of four individuals and one of only three. The students worked in their groups to build an effective query, using the key-words previously presented. The Queries used in data search are the ones that follow:

    

 ("Asthma"[Mesh] OR asthm*[tiab] OR "Asthma/prevention and control"[Mesh]) AND (child [MeSH]) AND (europe [MeSH] OR                         europe [tiab]).

 

 TITLE-ABS-KEY ((“Asthma” OR asthm* OR “Asthma/prevention AND control”) AND (child) AND (europe OR european))

 

Topic=(asthma) AND Topic=(control) AND Topic=(europe) AND Topic=(children)

   

    The third and final stage of the research is the DataBase Search. The chosen DataBases were drawn to each of the previously mentioned groups on February 26^th. Each group had from March 1^st until March 12^th to conclude the research and present the EndNote file containing the articles’ references. This task simply was to export all citations to a reference manager, the one used being EndNote X3 since it was easier to work with in order to keep track of articles and remove the duplicates.

    The number of articles obtained was 3071 in Pubmed, 571 in Scopus and 27 in Isi Web of Knowledge. Regarding the great number of articles found using Pubmed we decided that only one student was to be responsible for the exportation of Isi’s references, and the remaining three were included in the Pubmed group.

    After the removal of duplicates our total number of articles was 3335.

 

    Data Selection

    The references were divided, using EndNote, in four files of 830, give or take, which were randomly distributed by four groups of two students each. The groups read the titles and abstracts of the articles, excluding those they believed not to be essential to our review and writing down their motives for such exclusion. In cases of disagreement one of the three colleagues left was consulted.

    This process led to a total of 195 included articles and 3133 excluded.

    In the next phase, four different groups composed of two students were given 49 of the included articles in order to read, and by applying inclusion criteria:

•  studies made in children;

•  children being controlled in an European country;

• definition of asthma control is according to GINA's guidelines.

and exclusion criteria:

•  focusing only the methods of asthma control;
•  not written in English;
•  The study’s result referred to both adults and children combined;
•  The full text was not available [a],

 selected the final articles to be included in the study. Similarly, a third reviewer was added, when necessary.

    In the end of this phase we had included a total of 6 articles.

 

    However, after the presentation we realized that the number of articles obtained in the three databases were not in accord with each other.     For instance:

• Isi’s were too low;
• Pubmed’s were too many in comparison with Scopus’s, since the former is included in the latter.

    For these reasons, we decided to create new queries and although the results presented refer to our first attempt we intend to conduct later a second one in order to correct the mistake made. The new queries to be used shall be:

 

 (Asthma[Mesh] OR asthma[tiab]) AND (child [MeSH] OR child [tiab]) AND (control)).

TITLE-ABS-KEY(asthma) AND TITLE-ABS-KEY(control) AND ABS(child)

Topic=(asthma) AND Topic=(control) AND Topic=(children)

 

    The number of articles thus obtained was 6034 in Pubmed, 4948 in Scopus and 3587 in Isi Web of Knowledge.

    In this new attempt, we conducted the same methods as before; only the results changed. So, after removing the duplicates we ended up with 6672 articles and by the end of the Data Selection Phase, we included 6 articles.

    The Data Selection Methods are shown in the FlowCharts presented in Appendix.

 

    Quality Assessment

   This step was performed independently by two reviewers, according to the STROBE checklist ^[15].

   This specific checklist has a total of 22 items.                                                                      

 

Title	Author	Score
Cost, morbidity, and control of asthma in Hungary: The Hunair Study	Herjavecz I, N. G., Gyurkovits K, Magyar P, Dobos K, Nagy L, Alemao E, Ben-Joseph R.	17
Actual asthma control in a paediatric outpatient clinic population: do patients perceive their actual level of control?	Hammer SC, R. C., van Rij C, Heynens J, Droog R, Jöbsis Q, Hendriks HJ, Dompeling E.	13
Age-related differences in perceived asthma control in childhood: guidelines and reality	Kuehni CE, F. U.	15
Predictors of the persistence of childhood asthma.	Cabanas Rodriguez ER, G. B. F., Cabanas Rodriguez P, Leis R, Martinez B, Cabanas R, Valdes Cuadrado L, Tojo R.	13
Women, patients with severe asthma, and patients attended by primary care physicians, are at higher risk of suffering from poorly controlled asthma."	Badiola C, B. L., Plaza V, Prieto L, Molina J, Villa JR, Cimas E.	17
Predictors of asthma control in children from different ethnic origins living in Amsterdam.	Van Dellen QM, S. K., Bindels PJ, Ory FG, Bruil J, van Aalderen WM; PEACE Study Group.	16

 

 

 

 

 

 Data Extraction

 

    For each study selected, a reviewer extracted data to an Excel© spreadsheet and another one confirmed the information. Data on (I) year of publication; (II) author of study; (III) title of article; (IV) type of observational study; (V) number of participants included in the study, (VI) age of participants; (VII) gender of participants; (VIII) countries where control was performed; (IX) severity of asthma; (X) type of control; (XI) study quality; (XII) proportion values and (XIII) response rate was reunited extracted from original articles.

    The information was afterwards compiled in an SPSS Syntax by a single student. The variables to be created were previously discussed and the syntax created by three reviewers working together.