What are we reading now? An update on the papers published in the orthodontic literature (1999 - 2008).

Aims: To assess differences between articles published in the Journal of Orthodontics (JO) and European Journal of Orthodontics (EJO) from 1999 to 2008 and compare longitudinal publication profiles. Design: Retrospeclive, observational Methods: The main study examined articles from the American Journal of Orthodontics and Den tofacial Orthopedics and Angle Orthodontist alongside the JO and EJO. All journals were hand-searched to identify eligible articles. A random sample from these articles was obtained to provide 80% power to detect a 100% increase in the number of randomized controlled trials (RCTs) at the 5% level of significance. Each article was classified according to pre-determined criteria by one author (RG). Variations between journals were assessed using the chi-squared test or odds ratio (OR) and 95% confidence intervals (95% Results: A random sample of 425 articles was obtained from 4301 eligible articles, of which 113 were from the JO or EJO. About 34.5% of articles were from the JO and 66.5% the EJO. Statistically significant differences were found between the type (P<0.00l), subject (P=0.049), method/direction (P=0.038) and controls (P=0.006) of articles published in the two journals. When compared longitudinally the proportion of RCTs published between 1989 and 1993 (2.8%) and 1999-2008 (18.5%) was statistically significant (OR=8.0, 95% CI 2.8, 23.1). Statistically significant differences were seen over time in all aspects investigated. Conclusions: Statistically significant differences were found in the publication profiles of the two orthodontic journals during the period examined and longitudinally. A piece of clinical research was 8 times more likely to be an RCT during 1999-2008, compared to 1989-1993. [ABSTRACT FROM AUTHOR]