Skip to main content
Indian Journal of Anaesthesia logoLink to Indian Journal of Anaesthesia
. 2025 Aug 12;69(9):954–955. doi: 10.4103/ija.ija_842_25

Response to the “Comment on the interpretation of odds ratios in ‘association of frailty with postoperative outcomes’”

Rinu Raju 1, Pooja Singh 1,, Pranita Mandal 1, Vaishali Waindeskar 1, Sunaina T Karna 1
PMCID: PMC12377538  PMID: 40880970

Dear Editor,

We thank the reader comments[1] to our published manuscript,[2] the odds ratios (ORs) of 1.74 and 2.33 reported for general versus neuraxial anaesthesia were erroneously interpreted as “74 times” and “133 times” instead of 74% and 133% increase in odds of complications, respectively.

In Figure 3 of the published article,[2] the most significant difference is observed in Clavien-Dindo (CD) grade IV/intensive care unit (ICU) complications, where patients with modified frailty index (mFI) ≥0.27 who received general anaesthesia had significantly higher complication rates compared to those with neuraxial anaesthesia (P < 0.001). The visual perception biases in bar graphs can lead to overestimating bar heights and OR values.[3] In all the CD groups with mFI ≤0.27 and ≥0.27, patients had overlapping complications, such as two or three complications in the CD I group or one complication in the CD I group and another in the CD II group, leading to a probable overestimation of the OR. To address this, we have computed the adjusted OR (AOR) using a logistic regression model[4] for patients having mFI ≥0.27 undergoing neuraxial and general anaesthesia. The AOR is 1.55, indicating that patients undergoing general anaesthesia have a 55% increased risk of complications compared to those undergoing neuraxial anaesthesia. Thus, it further supports our result that in patients with high mFI, the complication risk is higher in general anaesthesia compared to neuraxial anaesthesia.

Authors contributions

Author name in FULL Authors contributions: Role (Concepts, Design, Definition of intellectual content, investigation, manuscript writing, etc.) [Add for all authors separately here]
RR Concept, Design
PS Concept, Definition of intellectual content, Manuscript writing
PM Manuscript Review
VW Manuscript Review
STK Manuscript Writing, Manuscript review

Conflicts of interest

There are no conflicts of interest.

Funding Statement

Nil.

REFERENCES

  • 1.“Comment on the Interpretation of Odds Ratios in ‘Association of Frailty with Postoperative Outcomes” by Raju et al. (ija_834_25) [Google Scholar]
  • 2.Raju R, Singh P, Mandal P, Waindeskar V, Karna ST. Association of frailty with postoperative outcomes in patients undergoing elective non-malignant abdominal surgeries under general or neuraxial anaesthesia: A prospective observational cohort study. Indian J Anaesth. 2025;69:693–9. doi: 10.4103/ija.ija_903_24. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 3.Xiong C, Ceja CR, Ludwig CJH, Franconeri S. Biased average position estimates in line and bar graphs: Underestimation, overestimation, and perceptual pull. IEEE Trans Vis Comput Graph. 2020;26:301–10. doi: 10.1109/TVCG.2019.2934400. [DOI] [PubMed] [Google Scholar]
  • 4.Karlson KB, Popham F, Holm A. Marginal and conditional confounding using logits. Sociol Methods Res. 2023;52:1765–84. doi: 10.1177/0049124121995548. [DOI] [PMC free article] [PubMed] [Google Scholar]

Articles from Indian Journal of Anaesthesia are provided here courtesy of Wolters Kluwer -- Medknow Publications

RESOURCES