Has reporting of methods in animal studies in psychiatric research improved since the introduction of the ARRIVE guidelines?

Objective: Animal research has been dominated by poor methodology or poor reporting. The ARRIVE guidelines
were introduced in 2010 to increase the quality of reporting in animal research. An evaluation by Baker et al (2014)
reported inadequate adherence to the ARRIVE guidelines by researchers and journal editors. We are undertaking
two systematic reviews to investigate harms from exposure to psychiatric drugs; one on long-term behavioral harms
from previous exposure to psychiatric drugs after a drug-free period and one on abnormal development of
reproductive organs from exposure to ADHD medication.
Method: Two independent observers assessed risk of bias due to randomization and blinding in studies included in
either of the two systematic reviews and published in 2011 or later. We used the ARRIVE guidelines for reporting
and the risk of bias tool presented by the Systematic Review Centre for Animal Experimentation (Netherlands) for
assessments.
Results: Sixteen of 58 studies included in the two systematic reviews were published in 2011 or later. Of these, two
studies reported to have randomized the animals to either intervention or control groups, no studies used random
housing to prevent influence on behavior from temperature and light differences, and one study used random
outcome assessment to prevent bias from diurnal variation. No caregivers were adequately described as being
blinded, and two studies described observers to be blinded.
Overall, the adherence to the ARRIVE guidelines was poor. The results showed us that animal psychiatric research
is as methodologically poor or poorly reported as studies published before introduction of the ARRIVE guidelines.
Conclusion: The implications from poor methodology in research or poor reporting are substantial: resources and
animals could be allocated to more useful purposes, and important knowledge about harms from psychiatric drugs is
delayed or hampered. We strongly endorse the use of the ARRIVE reporting guidelines in animal psychiatric
research. The ARRIVE guidelines should be introduced to researchers early in their education to carry out
responsible methodological study design. Funding bodies, ethics committees, regulatory agencies and journal
editors should demand adherence. Actions to improve guideline implementation and adherence at all institutions
implicated in animal research are clearly necessary.