You will be provided with the titles and abstracts of a collection of medical RCT reports studying a clinical question -- for instance, the efficacy of an intervention on some medical outcome. Please write a few sentences synthesizing the findings of these reports, which could serve as a conclusion section for a systematic review article. Your response should not include any other text. The RCT reports are below.



Title 1:
Xylitol administered only during respiratory infections failed to prevent acute otitis media.
Abstract 1:
As regular administration of xylitol had been effective in preventing acute otitis media (AOM) in children, we tested whether xylitol administered only at times of acute respiratory infection (ARI) reduces the occurrence of AOM.
                Healthy children (N = 1277) were recruited from child care centers and randomized after screening with tympanometry to receive either control mixture (n = 212), xylitol mixture (n = 212), control chewing gum (n = 280), xylitol chewing gum (n = 286), or xylitol lozenges (n = 287) during an ARI. The trial was randomized and double blinded within the mixture and chewing gum groups. The parents began administering the products to their children at the onset of symptoms of ARI. The follow-up lasted until resolution of the symptoms or up to 3 weeks.
                A total of 1253 of the 1277 randomized children were eligible for the analysis. Altogether, 980 (78%) of 1253 children had at least 1 episode of ARI during the 4 months that the trial lasted. The occurrence of AOM during this episode was 34 (20.5%) of 166 in the xylitol mixture group, as compared with 32 (20.4%) of 157 among the children who received the control mixture. Among the older children who received control chewing gum, xylitol chewing gum, or xylitol lozenges, AOM was experienced by 24 (11.0%) of 218, 31 (14.1%) of 220, and 34 (15.5%) of 219, respectively. None of the differences between the groups was statistically significant.
                Xylitol administered only during an ARI was ineffective in preventing AOM.


Title 2:
A novel use of xylitol sugar in preventing acute otitis media.
Abstract 2:
Xylitol, a commonly used sweetener, is effective in preventing dental caries. As it inhibits the growth of pneumococci, we evaluated whether xylitol could be effective in preventing acute otitis media (AOM).
                Altogether, 857 healthy children recruited from day care centers were randomized to one of five treatment groups to receive control syrup (n = 165), xylitol syrup (n = 159), control chewing gum (n = 178), xylitol gum (n = 179), or xylitol lozenge (n = 176). The daily dose of xylitol varied from 8.4 g (chewing gum) to 10 g (syrup). The design was a 3-month randomized, controlled trial, blinded within the chewing gum and syrup groups. The occurrence of AOM each time the child showed any symptoms of respiratory infection was the main outcome.
                Although at least one event of AOM was experienced by 68 (41%) of the 165 children who received control syrup, only 46 (29%) of the 159 children receiving xylitol syrup were affected, for a 30% decrease (95% confidence interval [CI]: 4.6%-55.4%). Likewise, the occurrence of otitis decreased by 40% compared with control subjects in the children who received xylitol chewing gum (CI: 10.0%-71.1%) and by 20% in the lozenge group (CI: -12.9%-51.4%). Thus, the occurrence of AOM during the follow-up period was significantly lower in those who received xylitol syrup or gum, and these children required antimicrobials less often than did controls. Xylitol was well tolerated.
                Xylitol sugar, when given in a syrup or chewing gum, was effective in preventing AOM and decreasing the need for antimicrobials.


Title 3:
Xylitol chewing gum in prevention of acute otitis media: double blind randomised trial.
Abstract 3:
To examine whether xylitol, which reduces the growth of Streptococcus pneumoniae, might have clinical importance in the prevention of acute otitis media.
                A double blind randomised trial with xylitol administered in chewing gum.
                Eleven day care nurseries in the city of Oulu. Most of the children had had problems with recurrent acute otitis media.
                306 day care children: 149 children in the sucrose group (76 boys; mean (SD) age 4.9 (1.5) years) and 157 in the xylitol group (80 boys; 5.0 (1.4) years).
                Either xylitol (8.4 g a day) or sucrose (control) chewing gum for two months.
                The occurrence of acute otitis media and antimicrobial treatment received during the intervention and nasopharyngeal carriage of S pneumoniae.
                During the two month monitoring period at least one event of acute otitis media was experienced by 31/149 (20.8%) children who received sucrose compared with 19/157 (12.1%) of those receiving chewing gum containing xylitol (difference 8.7%; 95% confidence interval 0.4% to 17.0%; P = 0.04). Significantly fewer antimicrobials were prescribed among those receiving xylitol: 29/157 (18.5%) children had at least one period of treatment versus 43/149 (28.9%) (difference 10.4%; 0.9% to 19.9%; P = 0.032). The carriage rate of S pneumoniae varied from 17.4% to 28.2% with no difference between the groups. Two children in the xylitol group experienced diarrhoea, but no other adverse effects were noted among the xylitol users.
                Xylitol seems to have a preventive effect against acute otitis media.


Title 4:
Failure of xylitol given three times a day for preventing acute otitis media.
Abstract 4:
Xylitol administered regularly 5 times a day after each meal is successful in preventing acute otitis media (AOM) in children, but if given only during respiratory infections it is ineffective against AOM. To find a more convenient dosing regimen, we tested whether xylitol administered 3 times a day reduces the occurrence of AOM.
                In this 3-month randomized, double-blind trial, 663 healthy day care children were randomized to receive either a control product (n = 331) or xylitol (n = 332). Xylitol was given in chewing gum or in a mixture 3 times a day, the daily dose being 0.5 g in the control group and 9.6 g in the xylitol group. The occurrence of the first AOM diagnosed during any period of respiratory symptoms during the follow-up was the main outcome measure.
                At least one AOM episode was diagnosed in 98 of the 331 children who received control products (30%) and in 94 of the 332 who received xylitol products (28%). A total of 142 episodes of AOM were diagnosed in the control group compared with 156 in the xylitol group. The differences were not statistically significant.
                Xylitol given regularly 3 times a day for 3 months during the respiratory infection season failed to prevent AOM.
There is fair evidence that the prophylactic administration of xylitol among healthy children attending day care centres reduces the occurrence of AOM by 25%. This meta-analysis is limited since the data arise from a small number of studies, mainly from the same research group.