Jenkins et al. Chiropractic & Manual Therapies (2022) 30:12 https://doi.org/10.1186/s12998-022-00421-9 LETTER TO THE EDITOR Reply to the letter to the editor: “What are the efects of diagnostic imaging on clinical outcomes in patients with low back pain presenting for chiropractic care? A matched observational study.” Jenkins et al., Chiropractic & Manual Therapies 2021;29:46 Hazel J. Jenkins 1* , Alice Kongsted 2 , Simon D. French 4 , Tue Secher Jensen 2,3,5 , Klaus Doktor 2,3 , Jan Hartvigsen 2,3 and Mark Hancock 4 © The Author(s) 2022. Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/. The Creative Commons Public Domain Dedication waiver (http://creativecom- mons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated in a credit line to the data. Reply to the letter to the editor We thank Dr Lopes for his interest in our study [1] and his recognition of its importance. We agree that our study did not specifcally describe treatment or how the imaging performed may (or may not) have infuenced treatment. As we stated in the origi- nal article, our aim was to determine whether treatment outcomes (e.g. pain intensity, disability) changed when the chiropractor decided to use imaging as part of patient management, not to explore how imaging may afect the specifc treatment provided by chiropractors. Te primary purpose of imaging, as recommended by clinical practice guidelines, is to rule out serious pathol- ogy [2]. In our study, the mean number of patients referred for imaging was 24% and up to 64% of patients were referred for imaging depending on the individual chiropractor. Terefore, it is likely that imaging was not being performed to rule out serious pathology alone, which occurs in less than 1% of low back pain presen- tations [3]. Rather, some chiropractors may have been referring for imaging when they thought it likely to change or inform patient management. In our study we attempted to approximate randomi- sation by matching patients on known baseline data, including intention to use spinal manipulation. By doing this we attempted to make the matched groups as simi- lar as possible so that the chiropractor’s decision to refer, or not refer, for imaging would be the key diference between the groups. We also controlled for the chiro- practor in the analysis to account for possible diferences between individual chiropractors. As described in the limitations section of our article, we could not account for unmeasured variables; however, we considered that key variables likely to afect the decision to refer for imaging were accounted for. For these reasons we believe that our conclusion that the decision to refer for imaging did not result in bet- ter clinical outcomes is appropriate. A randomised controlled trial is indicated to further explore this area without the limitations inherent in a matched observa- tional design. We also agree with Dr Lopes that future studies to describe how imaging informs treatment and whether diferent types of imaging assessment change clinical Open Access *Correspondence: hazel.jenkins@mq.edu.au 1 Faculty of Medicine, Health and Human Sciences, Macquarie University, Room 2232, Level 2, 75 Talavera Rd, Sydney 2109, Australia Full list of author information is available at the end of the article