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: Retrospective, observational.

METHODS: The main study examined articles from the American Journal of Orthodontics and Dentofacial 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% CI).

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<0·001), 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.