Comparison of conference abstracts and full-text publications of randomized controlled trials presented at four consecutive World Congresses of Pain: Reporting quality and agreement of results.

BACKGROUND: Conference abstracts are a potential source of new and relevant information about randomized controlled trials (RCTs). However, their dependability is questionable. The objectives of this study were to quantify the agreement between results of RCTs reported in abstracts presented at the four most recent World Congresses on Pain (WCP) and their corresponding full publications, and to analyse the completeness of reporting in those abstracts. METHODS: To identify RCTs, we screened all abstracts presented at four WCPs from 2008 to 2014. Two independent authors identified corresponding full-text reports published through August 2016. Data about the main outcomes in each abstract and full publication were extracted, including the outcome domains and numerical results reported. We reported discordance between abstracts and full texts. We evaluated abstracts against the CONSORT for Abstracts checklist. RESULTS: Approximately half of the 614 included abstracts had been fully published. Among the 306 abstract/publication pairs, eight pairs were not evaluable, and in the remaining 298 we found some form of discordance in 31% of the cases; the majority of discordances were quantitative, i.e. numerical results were different in the two locations, but with the same direction of effect. In the abstract-publication pairs where the abstract presented only preliminary/interim results, 79% had some form of discordance, mostly quantitative. CONCLUSIONS: The reporting quality of the 614 abstracts was suboptimal; the median adherence across all domains for all abstracts was 26%. In conclusion, conference abstracts of pain research are often not necessarily dependable information. Authors should be required to report abstracts according to reporting guidelines. SIGNIFICANCE: Abstracts of RCTs addressing pain are not often dependable information sources; half of them are not published, their reporting quality is suboptimal. When published, 30% of abstracts-full text pairs have discordant results, with 78% discordance when abstracts present preliminary results.

The effects of intraganglionic injection of calcium/calmodulin-dependent protein kinase II inhibitors on pain-related behavior in diabetic neuropathy.

Calcium/calmodulin-dependent protein kinase II (CaMKII) has been implicated in the transmission of nociceptive input in diabetic neuropathy. The aim of this study was to test whether intraganglionic (i.g.) injection of CaMKII inhibitors may alleviate pain-related behavior in diabetic rats. Diabetes was induced in Sprague-Dawley rats using 55 mg/kg streptozotocin intraperitoneally. Two weeks after diabetes induction, CaMKII inhibitors myristoil-AIP and KN93 were injected directly into the right L5 dorsal root ganglion (DRG). Behavioral testing with mechanical and thermal stimuli was performed before induction of diabetes, the day preceding the injection, as well as 2 and 24h after the i.g. injection. The expression of total CaMKII and its alpha isoform in DRG neurons was analyzed using immunohistochemistry. CaMKII inhibitors attenuated pain-related behavior in a modality-specific fashion. Attenuation of nociceptive behavior was accompanied with a corresponding decrease of CaMKII alpha expression in DRG neurons on the side of injection. A significant decrease of CaMKII alpha expression was seen in small- and medium-sized neurons. In conclusion, our study provides evidence that CaMKII inhibitors are potential pharmacological agents that should be further explored for treatment of diabetic neuropathy symptoms.