F1000Research F1000Research 2046-1402 F1000 Research Limited London, UK 10.12688/f1000research.144250.1 Study Protocol Articles A cross-sectional study of neutrophil to lymphocyte ratio as a prognostic marker in acute organophosphorus poisoning in a tertiary care hospital in Central India

[version 1; peer review: 2 not approved]

 Pradeep Utkarsh Methodology Project Administration Visualization Writing – Original Draft Preparation Writing – Review & Editing https://orcid.org/0009-0007-5030-7958 a 1 Mahajan Dr Satish Methodology Project Administration Writing – Original Draft Preparation Writing – Review & Editing 1 Medicine, Datta Meghe Institute of Higher Education & Research, Wardha, 442001, India utkarsh11nov@gmail.com

No competing interests were disclosed.

 25 4 2024 2024 13 387 12 4 2024 Copyright: © 2024 Pradeep U and Mahajan DS 2024 This is an open access article distributed under the terms of the Creative Commons Attribution Licence, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Background

Acute organophosphorus poisoning remains a significant public health concern, with variable clinical outcomes. Prognostic markers are crucial for patient management and risk stratification. This study aims to investigate the Neutrophil Lymphocyte Ratio (NLR) as a potential prognostic marker and its associations with severity and clinical outcomes in acute organophosphorus poisoning.

 Methods

This cross-sectional observational study will be conducted over two years, involving patients presenting with acute organophosphorus poisoning in the Medicine Ward and Intensive Care Unit of DMIHER Wardha. Informed consent will be obtained, and detailed clinical assessments, laboratory investigations, and NLR calculations will be performed. The Nambaet, Peradeniya, and Bardin classification scales will be used to measure severity. Statistical methods will be applied to explore the relationships between NLR, clinical parameters, and clinical outcomes, including descriptive statistics, bivariate analysis, correlation analysis, multivariate regression, and ROC analysis.

 Expected Results

The study is anticipated to elucidate the role of NLR as a prognostic marker in acute organophosphorus poisoning. Initial assessments and correlations between NLR and clinical parameters will be presented. The predictive capability of NLR for clinical outcomes, including the need for ventilatory support and length of hospital stay, will be explored. Agreement and discrepancies between the classification scales will be evaluated.

 Organophosphorus Poisoning Neutrophil to Lymphocyte Ratio Prognostic Marker Severity Classification Clinical Outcomes Risk Stratification The author(s) declared that no grants were involved in supporting this work. Introduction

Organophosphorus compounds are widely used in agriculture, industry, and households, playing a pivotal role in pest control and producing various essential products. However, their ubiquitous presence poses a considerable risk to human health, primarily due to unintentional exposures and deliberate self-harm incidents. 1 Acute organophosphorus poisoning, resulting from the inhibition of acetylcholinesterase and the accumulation of acetylcholine, leads to a broad spectrum of clinical manifestations, ranging from mild symptoms to life-threatening toxicity. Effective management of acute organophosphorus poisoning demands early identification of severity and prognostication, as it significantly influences treatment decisions and clinical outcomes. 2

Identifying reliable prognostic markers has been an ongoing pursuit in toxicology, aiming to enhance risk stratification and guide therapeutic strategies. 3 The Neutrophil to Lymphocyte Ratio (NLR), an inflammatory marker, has gained recognition for its potential utility in various medical conditions. Its role as a prognostic marker in acute organophosphorus poisoning has piqued interest due to its simplicity and availability as part of routine blood tests. 4

This cross-sectional study investigates the NLR as a potential prognostic marker in acute organophosphorus poisoning. By assessing its associations with the severity of poisoning and clinical outcomes, we aim to contribute to a deeper understanding of NLR’s role in patient management. Our study will utilise established severity classification scales, including the Nambaet, Peradeniya, and Bardin classifications, to comprehensively evaluate the severity of poisoning and to compare their agreement and discrepancies.

In the era of evidence-based medicine, the quest for novel prognostic markers that can facilitate informed clinical decisions is of paramount importance. This study endeavours to shed light on the utility of the NLR as a potential prognostic marker in acute organophosphorus poisoning, aiming to improve patient outcomes and refine therapeutic approaches in this critical area of toxicology.

Aim

This study aims to investigate the potential utility of the Neutrophil Lymphocyte Ratio as a prognostic marker in patients with acute organophosphorus poisoning.

 Objectives

To determine the Neutrophil Lymphocyte Ratio in patients with acute organophosphorus poisoning.

To evaluate the relationship between the Neutrophil Lymphocyte Ratio and the severity of organophosphorus poisoning as classified by the Nambaet classification, Peradeniya organophosphorus poisoning scale, and Bardin classification.

To assess whether an elevated neutrophil-to-lymphocyte ratio is associated with the need for ventilatory support in these patients.

To investigate whether the Neutrophil to Lymphocyte Ratio is correlated with the dose of atropine administered to patients with acute organophosphorus poisoning.

To examine if the Neutrophil to Lymphocyte Ratio can predict the length of hospital stay in patients with acute organophosphorus poisoning.

Method Study design

This study employs a cross-sectional, observational design to investigate the Neutrophil Lymphocyte Ratio as a potential prognostic marker in patients with acute organophosphorus poisoning. Data will be collected at a single time point setup for the 2023-2024 period.

 Study population

The study population consists of patients who have presented with acute organophosphorus poisoning. These patients will be recruited from the Medicine Ward and Medicine Intensive Care Unit of DMIHER Wardha.

 Place of study

The study will be conducted in the Acharya Vinoba Bhave Rural Hospital Department of Medicine.

 Inclusion criteria

Patients with a confirmed history of oral ingestion of organophosphorus compounds.

Patients who present at the casualty department or are admitted to the Medicine Ward or Medicine Intensive Care Unit of DMIHER Wardha within 24 hours of organophosphorus compound ingestion.

Patients who provide informed consent to participate in the study.

Patients of all age groups, regardless of gender.

Exclusion criteria

Patients who decline to provide informed consent.

Patients exposed to poisons or compounds other than organophosphorus.

Patients with severe chronic comorbidities, including liver cirrhosis, symptomatic heart failure (New York Heart Association class III or IV), end-stage chronic kidney disease (on regular hemodialysis), and chronic obstructive pulmonary disease (COPD).

Patients diagnosed with malignancies.

Bias

Selection bias: There is a risk that patients who agree to participate in the study may only be representative of some patients with acute organophosphorus poisoning. To mitigate this bias, researchers should use a random or consecutive sampling approach when recruiting participants to ensure that the sample is as representative as possible.

Information bias: This can occur if there are inaccuracies or inconsistencies in data collection or measurements. To minimise this bias, researchers should employ standardised data collection tools and procedures, ensure that data collectors are trained, and perform regular quality checks on the collected data.

Observer bias: In the context of this study, observer bias could occur when healthcare providers assess and classify patients differently based on their judgments. To address this, researchers should provide clear guidelines and criteria for assessing organophosphorus poisoning severity, ensuring the assessment is consistent among different observers.

Enrollment process

Patient identification: Patients admitted to the Medicine Ward or Medicine Intensive Care Unit of DMIHER Wardha with a history of acute organophosphorus poisoning will be identified for enrollment.

Informed consent: The first step in enrollment is obtaining informed consent. Patients or their legally authorised representatives will be approached, and the study will be explained in detail, including its purpose, procedures, risks, and benefits. Consent forms in the appropriate language will be provided to the patients or representatives. If the patient is not in a state to provide informed consent, it will be obtained from their relatives.

Screening for inclusion and exclusion criteria: After obtaining informed consent, patients will be screened to ensure they meet the inclusion and exclusion criteria defined in the study protocol. Patients who meet these criteria will proceed to the next steps.

Baseline data collection: Upon enrollment, baseline data will be collected, which includes demographic information, clinical history, and relevant medical information.

Clinical assessments: Patients will undergo clinical assessments, including vital signs and a physical examination. These assessments will provide the necessary data for the classification scales (Nambaet classification, Peradeniya classification, and Bardin classification).

Blood sample collection: Blood samples will be collected during the study procedures. These samples will be used to determine the Neutrophil Lymphocyte Ratio, which is one of the main parameters of interest in the study.

Grading of severity: The severity of organophosphorus poisoning will be graded using the three classification scales. Clinical parameters and laboratory results will be considered in these assessments.

Data recording: All collected data, including clinical assessments, blood test results, and classification scale scores, will be carefully recorded in designated proforma or electronic data management systems.

Follow-up: Depending on the study objectives, patients may be followed up during their hospital stay to assess outcomes such as the need for ventilatory support, dose of atropine, and hospital stay duration.

Data analysis: After data collection is complete, the collected data will be analysed to address the study’s objectives and assess the Neutrophil Lymphocyte Ratio as a prognostic marker in acute organophosphorus poisoning.

Data collection process

Informed consent: Following a detailed explanation of the study to prospective participants, informed consent will be meticulously acquired from those individuals who meet the study’s inclusion criteria.

Clinical assessment in intensive care: Within the confines of the Medicine Intensive Care Unit and ward, subjects will meticulously evaluate their vital signs. This will entail the thorough monitoring of critical physiological parameters.

Laboratory blood investigations: Blood tests in the centralised clinical laboratory will be conducted, including a complete blood count (CBC) and potentially other relevant assays. These laboratory results will be instrumental in assessing the participants’ health status.

Data recording: All pertinent values and findings derived from these assessments will be meticulously recorded in dedicated proforma, maintaining a precise record of the patient’s clinical data.

Clinical history collection: A comprehensive clinical history, particularly related to the organophosphorus poisoning episode, will be systematically gathered from the participants. This will be performed per the pre-established inclusion and exclusion criteria.

Patient guidance: Participants will be comprehensively briefed on the importance of ongoing vital sign monitoring and further scheduled blood investigations. Clear instructions will be provided to ensure their understanding and compliance with these critical aspects of care.

Blood sample collection: In line with the study’s requirements, blood samples will be skillfully obtained from the study subjects, adhering to the established medical protocols and with due regard for patient comfort.

Severity grading: The severity of organophosphorus poisoning will be meticulously graded by employing three distinct classification systems, namely the Nambaet classification, the Peradeniya classification, and the Bardin classification. These classifications provide a multidimensional assessment of the patient’s clinical condition.

Nambaet classification: This evaluation method will involve a thorough assessment of various clinical parameters and the measurement of acetylcholinesterase levels to determine the severity of organophosphorus poisoning according to the Nambaet classification. 5

Peradeniya classification: The Peradeniya classification will be assigned based on the assessment of various clinical parameters, and specific scores will be allocated for each parameter, allowing for a more comprehensive understanding of the patient’s condition. 6

Bardin classification: The Bardin classification employs a criterion-based system, where the presence of two or more specific criteria will lead to assigning a specific grade. Patients who do not meet at least two criteria will be placed in the preceding category. This approach provides a nuanced assessment of severity based on clinical criteria. 7

Initial assessment: Upon admission, all three classification scales will be meticulously applied to the study participants, allowing for an early and comprehensive evaluation of their condition and providing a valuable baseline for further analysis. This initial assessment is a critical reference point for the study’s objectives.

Sample size

Sample size: Minimum sample size required

Formula N = Z 1 − α / 2 2 ∗ p ∗ ( 1 − p ) D 2 . Z 1 − α / 2 = 1.96 , at 5% level of significance

P = Proportion of death for organ phosphorous poisoning having Neutrophil lymphocyte ratio >12 = 10.2% (As per reference article 4 )

D = estimated error (6%) = 0.06 = ( 1.96 ) 2 ∗ ( 0.102 ) ∗ ( 1 − 0.898 ) / ( 0.06 ) 2 = 98

Statistical method

The study will employ diverse statistical techniques to analyse the data comprehensively. Initially, descriptive statistics will be harnessed to provide a clear snapshot of the study population, offering insights into baseline characteristics. This will encompass measures such as means, standard deviations, medians, interquartile ranges for continuous variables, and frequencies and percentages for categorical variables. Bivariate analysis will be pivotal in exploring relationships between different variables. For instance, the Neutrophil to Lymphocyte Ratio will be scrutinised across severity categories using appropriate statistical tests like t-tests, ANOVA, or non-parametric tests tailored to the data distribution. Correlation analysis, featuring statistical measures like Pearson’s correlation coefficient or Spearman’s rank correlation, will unveil the intricate relationships between continuous variables, including the Neutrophil Lymphocyte Ratio and other pertinent clinical parameters.

In cases where independence and associations are sought, multivariate regression models will come into play. Multiple linear regression will uncover factors associated with the Neutrophil Lymphocyte Ratio. In contrast, logistic regression will predict outcomes such as the need for ventilatory support or the severity of organophosphorus poisoning. Given the utilisation of multiple classification scales (Nambaet, Peradeniya, Bardin), statistical tests like kappa statistics or concordance analyses will be instrumental in evaluating the agreement or disparities between these scales when assessing the severity of poisoning.

Subgroup analyses will investigate variations in associations between variables, such as the Neutrophil Lymphocyte Ratio and outcomes, within diverse study population subgroups, such as age, gender, or comorbid conditions. Furthermore, the diagnostic accuracy of the Neutrophil Lymphocyte Ratio will be quantified using Receiver Operating Characteristic (ROC) analysis, with the Area Under the ROC Curve (AUC) offering a measure of its prognostic potential. If relevant, survival analysis techniques, including Kaplan-Meier curves and Cox regression, will be employed to examine the link between the Neutrophil Lymphocyte Ratio and time-to-event outcomes like the length of hospital stay.

Sensitivity analyses will be conducted to ensure the robustness of results and assess the influence of potential confounders or bias. All statistical analyses will be executed with appropriate statistical software, such as SPSS version 23, under the guidance of qualified statisticians and proficient researchers well-versed in statistical methods. Significance levels will be diligently observed, with standard thresholds like p < 0.05 utilised to assess statistical significance.

 Ethical considerations

The Institutional Ethics Committee of Datta Meghe Institute of Higher Education and Research (DU) has granted its approval to the study protocol (Reference number: DMIHER (DU)/IEC/2022/941. Date:11-04-2023) CTRI registration- REF/2023/07/070131. Before commencing the study, we will obtain written informed consent from all participants, providing them with a comprehensive explanation of the study’s objectives.

 Dissemination

After the completion of the study, we will publish it in an indexed journal or conference.

 Study status

The study has yet to start after the publication of the protocol; we will start recruitment in the study.

 Discussion

Acute organophosphorus poisoning is a significant public health issue in many parts of the world, presenting clinicians with a diverse range of clinical manifestations and challenges in management. This study protocol outlines a comprehensive investigation into the potential use of the Neutrophil to Lymphocyte Ratio (NLR) as a prognostic marker in acute organophosphorus poisoning, aiming to shed light on its associations with disease severity and clinical outcomes.

The rationale for this study is grounded in the need for reliable prognostic markers to guide clinical decision-making in cases of acute organophosphorus poisoning. A review of existing literature reveals that despite advances in the management of poisoning cases, identifying markers that can help predict patient outcomes remains a critical research frontier. 8 The systemic inflammation response, as represented by the NLR, has been studied extensively in various medical conditions, including poisoning scenarios. 9 , 10 By delving into the relationship between NLR and organophosphorus poisoning, this study aligns itself with the broader research exploring the predictive potential of NLR in clinical settings.

Our study’s methodological rigor, including a cross-sectional design and a sizable sample size, will bolster the reliability of the findings. Consistent with prior studies, 11 we anticipate that NLR will be associated with the severity of poisoning, reflected in the clinical parameters and the classification scales used in this study. In line with international guidelines, 12 , 13 this approach ensures that the grading of poisoning severity is both comprehensive and comparable, providing a foundation for assessing the utility of NLR as an additional prognostic tool.

This study’s findings will contribute to a growing body of research on NLR in clinical prognostication, with relevance extending beyond organophosphorus poisoning. NLR has been previously identified as a prognostic marker in a range of medical conditions, such as acute kidney injury, 14 cardiovascular diseases, 15 and sepsis, 16 underscoring its versatility in clinical prediction. By exploring its applicability in the context of poisoning, this study adds a valuable dimension to the ongoing discourse on NLR as a universal prognostic marker.

Furthermore, this protocol aligns with the call for further research into acute poisoning scenarios, particularly those involving organophosphorus compounds. 17 Acute poisoning can lead to rapid clinical deterioration, making early prognostication crucial for timely and effective interventions. 18 As such, the results of this study could hold substantial implications for clinicians, public health practitioners, and policymakers, with the potential to influence clinical guidelines for organophosphorus poisoning management.

 Data availability

No data are associated with this article.

 References Chataut J Adhikari RK Sinha NP : Pattern of organophosphorous poisoning: a retrospective community based study. Kathmandu Univ Med J KUMJ. 2011;9:31–34. 22610865 10.3126/kumj.v9i2.6284 Blain PG : Organophosphorus poisoning (acute). BMJ Clin Evid. 2011;2011:2102. Singh S Kaushik AC Gupta H : Identification of prognostic markers and potential therapeutic targets using gene expression profiling and simulation studies in pancreatic cancer. Curr Comput Aided Drug Des. 14 September 2023;20:955–973. 37711100 10.2174/1573409920666230914100826 Mu Y Hu B Gao N : Prognostic value of the neutrophil-to-lymphocyte ratio in acute organophosphorus pesticide poisoning. Open Life Sci. 2021;16:703–710. 34307885 10.1515/biol-2021-0069 PMC8284330 Peter JV Sudarsan TI Moran JL : Clinical features of organophosphate poisoning: A review of different classification systems and approaches. Indian J Crit Care Med Peer-Rev Off Publ Indian Soc Crit Care Med. 2014;18:735–745. 25425841 10.4103/0972-5229.144017 PMC4238091 Malaviya NB Parikh R Pancholi K : Assessment of the Peradeniya Organophosphorus Poisoning Scale as a Severity and Prognostic Marker in Patients With Acute Organophosphorus Poisoning Presenting to an Emergency Medicine Department. Cureus. 2023;15:e40277. 37448435 10.7759/cureus.40277 PMC10336367 Bardin PG Van Eeden SF : Organophosphate poisoning: grading the severity and comparing treatment between atropine and glycopyrrolate. Crit Care Med. 1990;18:956–960. 10.1097/00003246-199009000-00010 Eddleston M Buckley NA Eyer P : Management of acute organophosphorus pesticide poisoning. Lancet. 2008;371:597–607. 17706760 10.1016/S0140-6736(07)61202-1 PMC2493390 Bi J-B Zhang J Ren Y-F : Neutrophil-to-lymphocyte ratio predicts acute kidney injury occurrence after gastrointestinal and hepatobiliary surgery. World J Gastrointest Surg. 2020;12:326–335. 32821341 10.4240/wjgs.v12.i7.326 PMC7407844 Williams DJ Hall M Auger KA : Association of White Blood Cell Count and C-Reactive Protein with Outcomes in Children Hospitalized for Community-acquired Pneumonia. Pediatr Infect Dis J. 2015;34:792–793. 25961893 10.1097/INF.0000000000000724 PMC4654105 Balta S Ozturk C : The platelet-lymphocyte ratio: A simple, inexpensive and rapid prognostic marker for cardiovascular events. Platelets. 2015;26:680–681. 25549287 10.3109/09537104.2014.979340 Sperduto PW Kased N Roberge D : Summary Report on the Graded Prognostic Assessment: An Accurate and Facile Diagnosis-Specific Tool to Estimate Survival for Patients With Brain Metastases. J Clin Oncol. 2012;30:419–425. 22203767 10.1200/JCO.2011.38.0527 PMC3269967 Malaviya NB Parikh R Pancholi K : Assessment of the Peradeniya Organophosphorus Poisoning Scale as a Severity and Prognostic Marker in Patients With Acute Organophosphorus Poisoning Presenting to an Emergency Medicine Department. Cureus. 2023;15:e40277. 37448435 10.7759/cureus.40277 PMC10336367 Jahan I Ahmed R Ahmed J : Neutrophil-lymphocyte ratio in Guillain-Barré syndrome: A prognostic biomarker of severe disease and mechanical ventilation in Bangladesh. J Peripher Nerv Syst JPNS. 2023;28:47–57. 36700342 10.1111/jns.12531 PMC10155239 Diniz LR Lima SG de Amorim Garcia JM de : Neutrophil to Lymphocyte Ratio as a Prognostic Predictor in Older People With Acute Coronary Syndrome. Angiology. 2019;70:264–271. 30153747 10.1177/0003319718796565 Jeon TJ Park JY : Clinical significance of the neutrophil-lymphocyte ratio as an early predictive marker for adverse outcomes in patients with acute pancreatitis. World J Gastroenterol. 2017;23:3883–3889. 28638228 10.3748/wjg.v23.i21.3883 PMC5467074 Preventing suicide: a resource for pesticide registrars and regulators.Accessed: October 23, 2023. Reference Source Gunnell D Eddleston M Phillips MR : The global distribution of fatal pesticide self-poisoning: Systematic review. BMC Public Health. 2007;7:357. 18154668 10.1186/1471-2458-7-357 PMC2262093 10.5256/f1000research.158011.r305572 Reviewer response for version 1 Kumar Deepak 1 Referee https://orcid.org/0000-0001-6343-6774 PGIMER, Chandigarh, India

Competing interests: No competing interests were disclosed.

 22 8 2024 Copyright: © 2024 Kumar D 2024 This is an open access peer review report distributed under the terms of the Creative Commons Attribution Licence, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. recommendation reject

Dear Editor

I have gone through the manuscript (study protocol) titled “A cross-sectional study of neutrophil to lymphocyte ratio as a prognostic marker in acute organophosphorus poisoning in a tertiary care hospital in Central India”.

Following are my comments for consideration (Major Revision)

Several studies are already available which showed the role of neutrophil-to-lymphocyte ratio (NLR) as a prognostic marker in acute organophosphorus poisoning with detailed method/protocol ( https://www.sciencedirect.com/science/article/abs/pii/S0736467914005034 file:///C:/Users/Dr%20Deepak%20Kumar/Downloads/5-OA-Basanta+Gauli.pdf, https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8284330/ ).

Please elaborate.

 

Under study status it is mentioned as

“The study has yet to start after the publication of the protocol; we will start recruitment in the study.”

               However, under study design it is mentioned as

                              “Data will be collected at a single time point setup for the 2023-2024 period.”

Considering the fact that it is mid-August 2024, when will the authors start the work and complete it within 2023-2024 period. So kindly revise the relevant content in the manuscript and its ethical approval accordingly.

 

Include the statement that the work will be carried out following the tenets of the Helsinki Declaration.

 

How the diagnosis of organophosphorus pesticide exposure will be carried out? Or in other words which method was used to find out the confirmed cases of  OP poisoning? How the authors confirm the inclusion and exclusion criteria. Which parameter will be considered for this?

  

Estimation of AChE activity is of the method for understanding OP poisoning. However, both organophosphorus (OP) and organocarbamates (OC) inhibit AChE activity ( https://pubmed.ncbi.nlm.nih.gov/37805177/ ). Then how do the authors distinguish OP cases from OC. Please address this issue. This should be properly mentioned in the protocol.

Under objectives, it is mentioned as under

 “To investigate whether the Neutrophil to Lymphocyte Ratio is correlated with the dose of atropine administered to patients with acute organophosphorus poisoning.”

In cases where organophosphate poisoning is on the differential but not confirmed, a trial of atropine is generally administered ( https://www.ncbi.nlm.nih.gov/books/NBK470430/#:~:text=If%20organophosphate%20poisoning%20is%20on,suspicion%20of%20AChE%20inhibitor%20poisoning. ). Then how do the investigators access the control NLR value (i.e., value before administration of atropine). Please discuss.

 

Mention which clinical/biochemical parameters will be considered for assessment.   

Kindly include the following in the exclusion criteria:

 The patients who are on steroids, pregnant patients, and patients with blood disorders ( https://www.jcmc.com.np/jcmc/index.php/jcmc/article/download/1311/836 ).

Thanks

Is the study design appropriate for the research question?

Partly

Is the rationale for, and objectives of, the study clearly described?

Yes

Are sufficient details of the methods provided to allow replication by others?

Yes

Are the datasets clearly presented in a useable and accessible format?

Partly

Reviewer Expertise:

Point of care; Poisoning; Biotechnology; Analytical Biochemistry

I confirm that I have read this submission and believe that I have an appropriate level of expertise to state that I do not consider it to be of an acceptable scientific standard, for reasons outlined above.

References : Organophosphate Toxicity. 29261901 : PROGNOSTIC VALUE OF THE NEUTROPHIL-TO-LYMPHOCYTE RATIO IN ACUTE PESTICIDE POISONING. Journal of Chitwan Medical College .2023;13(2) : 10.54530/jcmc.1311 20-24 10.54530/jcmc.1311 : Prognostic value of the neutrophil-to-lymphocyte ratio in acute organophosphorus pesticide poisoning. Open Life Sci .2021;16(1) : 10.1515/biol-2021-0069 703-710 34307885 10.1515/biol-2021-0069 : Neutrophil-lymphocyte ratio in patients with pesticide poisoning. J Emerg Med .2014;47(3) : 10.1016/j.jemermed.2014.01.034 286-93 24958695 10.1016/j.jemermed.2014.01.034 : Organophosphorus and carbamate pesticides: Molecular toxicology and laboratory testing. Clin Chim Acta .2023;551: 10.1016/j.cca.2023.117584 117584 37805177 10.1016/j.cca.2023.117584 10.5256/f1000research.158011.r277315 Reviewer response for version 1 Venkatarao Epari 1 Referee https://orcid.org/0000-0002-1841-352X Department of Community Medicine, Institute of Medical & Sum Hospital, Siksha ‘O’ Anusandhan, Bhubaneswar, Odisha, India

Competing interests: No competing interests were disclosed.

 7 6 2024 Copyright: © 2024 Venkatarao E 2024 This is an open access peer review report distributed under the terms of the Creative Commons Attribution Licence, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. recommendation reject

This is a protocol for publication before the research is being conducted. It talks about finding the ability of NLR as a prognostic indicator in organophosphorus poisoning. NLR as a prognostic indicator has been studied extensively in recent times in various other clinical conditions including cancer. Hence, the ROL should look into this including the methodology followed to find its prostic value, which will add further knowledge to the existing body of knowledge. The outcome variables of the study should be well defined before conducting the research. This will help in the designing the study and calculation of an appropriate sample size. The sample size should be calculated using AUC in ROC analysis from published literature.

The outcome measures defined by the study's objectives will determine the role of appropriate statistical methods. The authors have not been able to spell out the outcome measures properly. Hence, the specificity of the use of statistical methods seems vague. This can lead to confusion at a later stage after data collection. Dummy tables and dummy analysis before the execution of the study will be useful.

The Review of Literature (ROL) lacks a finding of NLR as an inflammatory marker. There is literature available on NLR as a prognostic marker in cancer.

The authors have proposed data collection at a single time point, which will have a bias in the analysis as factors like time-to-intervention, dose-response, quality of care, etc., can not be accounted for in the analysis.

Finally, the sample size calculation is inappropriate as the study is NOT trying to find the prevalence of death among organophosphorus poisoning cases with NLR >12, rather with appropriate ROL, sample size calculation method has to be revisited.

Is the study design appropriate for the research question?

No

Is the rationale for, and objectives of, the study clearly described?

Yes

Are sufficient details of the methods provided to allow replication by others?

Partly

Are the datasets clearly presented in a useable and accessible format?

Not applicable

Reviewer Expertise:

Epidemiological studies, Validation studies.

I confirm that I have read this submission and believe that I have an appropriate level of expertise to state that I do not consider it to be of an acceptable scientific standard, for reasons outlined above.