Defining Diarrhea: A Population-Based Validation Study of Caregiver-Reported Stool Consistency in the Amhara Region of Ethiopia

Kristen Aiemjoy Francis I. Proctor Foundation, University of California, San Francisco, San Francisco, California;
Department of Epidemiology and Biostatistics, University of California, San Francisco, San Francisco, California;

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Solomon Aragie The Carter Center Ethiopia, Addis Ababa, Ethiopia;

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Sintayehu Gebresillasie The Carter Center Ethiopia, Addis Ababa, Ethiopia;

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Dionna M. Fry Francis I. Proctor Foundation, University of California, San Francisco, San Francisco, California;

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Adane Dagnew The Carter Center Ethiopia, Addis Ababa, Ethiopia;

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Dagnachew Hailu The Carter Center Ethiopia, Addis Ababa, Ethiopia;

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Melsew Chanyalew Amhara Regional Health Bureau, Bahir Dar, Ethiopia;

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Zerihun Tadesse The Carter Center Ethiopia, Addis Ababa, Ethiopia;

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Aisha Stewart The Carter Center, Atlanta, Georgia;

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Kelly Callahan The Carter Center, Atlanta, Georgia;

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Mathew Freeman Rollins School of Public Health, Emory University, Atlanta, Georgia;

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John Neuhaus Department of Epidemiology and Biostatistics, University of California, San Francisco, San Francisco, California;

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Benjamin F. Arnold Division of Epidemiology, School of Public Health, University of California, Berkeley, Berkeley, California

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Jeremy D. Keenan Francis I. Proctor Foundation, University of California, San Francisco, San Francisco, California;

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Diarrhea is a leading cause of death among children aged less than five years globally. Most studies of pediatric diarrhea rely on caregiver-reported stool consistency and frequency to define the disease. Research on the validity of caregiver-reported diarrhea is sparse. We collected stool samples from 2,398 children participating in two clinical trials in the Amhara region of Ethiopia. The consistency of each stool sample was graded by the child’s caregiver and two trained laboratory technicians according to an illustrated stool consistency scale. We assessed the reliability of graded stool consistency among the technicians, and then compared the caregiver’s grade with the technician’s grade. We also tested if the illustrated stool consistency scale could improve the validity of caregiver’s report. The weighted kappa measuring the agreement between the two laboratory technicians reached 0.90 after 500 stool samples were graded. The sensitivity of caregiver-reported loose or watery stool was 15.5% (95% confidence interval [CI]: 9.7, 24.2) and the specificity was 98.4% (95% CI 97.1, 99.1). With the illustrated scale, the sensitivity was 68.5% (95% CI: 58.5, 77.1) and the specificity was 86.1% (95% CI: 79.3, 90.9). The results indicate that caregiver-reported stool consistency using the terms “loose or watery” does not accurately describe stool consistency as graded by trained laboratory technicians. Given the predominance of using caregiver-reported stool consistency to define diarrheal disease, the low sensitivity identified in this study suggests that the burden of diarrheal disease may be underestimated and intervention effects could be biased. The illustrated scale is a potential low-lost tool to improve the validity of caregiver-reported stool consistency.

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Author Notes

Address correspondence to Kristen Aiemjoy, Proctor Foundation, University of California, San Francisco, 513 Parnassus Avenue, MedSci S309, P.O. Box 0412, San Francisco, CA 94143. E-mail: kristen.aiemjoy@ucsf.edu

Financial support: This study was supported by the National Institute of Health (NEI U10 EY016214), (NICHD F31 HD088070-01A1 [to K. A.]), and (NIAID 1K01AI119180 [to B. F. A.]); That Man May See and The Sara & Evan Williams Foundation; and Research to Prevent Blindness.

Authors’ addresses: Kristen Aiemjoy, Francis I. Proctor Foundation, University of California, San Francisco, San Francisco, CA, and Department of Epidemiology and Biostatistics, University of California, San Francisco, San Francisco, CA, E-mail: kristen.aiemjoy@ucsf.edu. Solomon Aragie, Sintayehu Gebresillasie, Adane Dagnew, Dagnachew Hailu, and Zerihun Tadesse, The Carter Center Ethiopia, Addis Ababa, Ethiopia, E-mails: solomon.aragie@cartercenter.org, sintayehugs@gmail.com, adane.dagnew@cartercenter.org, dagnachew.hailu@cartercenter.org, and zerihun.tadesse@cartercenter.org. Dionna M. Fry and Jeremy D. Keenan, Francis I. Proctor Foundation, University of California, San Francisco, San Francisco, CA, E-mails: dionna.fry@ucsf.edu and jeremy.keenan@ucsf.edu. Melsew Chanyalew, Amhara Regional Health Bureau, Bahir Dar, Ethiopia, E-mail: yeshiwork97@yahoo.com. Aisha Stewart and Kelly Callahan, The Carter Center, Atlanta, GA, E-mails: aisha.stewart@cartercenter.org and kelly.callahan@cartercenter.org. Mathew Freeman, Rollins School of Public Health, Emory University, Atlanta, GA, E-mail: matthew.freeman@emory.edu. John Neuhaus, Department of Epidemiology and Biostatistics, University of California, San Francisco, San Francisco, CA, E-mail: John.Neuhaus@ucsf.edu. Benjamin F. Arnold, Division of Epidemiology, School of Public Health, University of California, Berkeley, Berkeley, CA, E-mail: benarnold@berkeley.edu.

  • 1.

    World Health Organization, 2017. Diarrhoeal Disease Fact Sheet. Available at: http://www.who.int/mediacentre/factsheets/fs330/en/. Accessed July 13, 2017.

    • PubMed
    • Export Citation
  • 2.

    World Health Organization, 2015. Ethiopia: WHO Statistical Profile. Available at: http://www.who.int/gho/countries/eth.pdf?ua=1. Accessed October 15, 2017.

    • PubMed
    • Export Citation
  • 3.

    Institute for Health Metrics and Evaluation, 2017. Global Burden of Disease. Available at: http://ghdx.healthdata.org/. Accessed October 15, 2017.

    • PubMed
    • Export Citation
  • 4.

    Johnston BC, Shamseer L, da Costa BR, Tsuyuki RT, Vohra S, 2010. Measurement issues in trials of pediatric acute diarrheal diseases: a systematic review. Pediatrics 126: e222e231.

    • PubMed
    • Search Google Scholar
    • Export Citation
  • 5.

    World Health Organization. Diarrhea (definition and sequelae). Geneva, Switzerland, WHO. Available at: http://www.who.int/topics/diarrhoea/en/. Accessed October 15, 2017.

    • PubMed
    • Export Citation
  • 6.

    Clasen T, Schmidt WP, Rabie T, Roberts I, Cairncros S, 2007. Interventions to improve water quality for preventing diarrhoea: systematic review and meta-analysis. BMJ 334: 782.

    • PubMed
    • Search Google Scholar
    • Export Citation
  • 7.

    Cairncross S, Hunt C, Boisson S, Bostoen K, Curtis V, Fung IC, Schmidt WP, 2010. Water, sanitation and hygiene for the prevention of diarrhoea. Int J Epidemiol 39 (Suppl 1): i193i205.

    • PubMed
    • Search Google Scholar
    • Export Citation
  • 8.

    Clasen TF, Bostoen K, Schmidt WP, Boisson S, Fung IC, Jenkins MW, Scott B, Sugden S, Cairncross S, 2010. Interventions to improve disposal of human excreta for preventing diarrhoea. Cochrane Database Syst Rev CD007180.

    • PubMed
    • Search Google Scholar
    • Export Citation
  • 9.

    Prüss‐Ustün A et al. 2014. Burden of disease from inadequate water, sanitation and hygiene in low‐and middle‐income settings: a retrospective analysis of data from 145 countries. Trop Med Int Health 19: 894905.

    • PubMed
    • Search Google Scholar
    • Export Citation
  • 10.

    Wolf J et al. 2014. Systematic review: assessing the impact of drinking water and sanitation on diarrhoeal disease in low‐and middle‐income settings: systematic review and meta‐regression. Trop Med Int Health 19: 928942.

    • PubMed
    • Search Google Scholar
    • Export Citation
  • 11.

    Clasen TF, Alexander KT, Sinclair D, Boisson S, Peletz R, Chang HH, Majorin F, Cairncross S, 2015. Interventions to improve water quality for preventing diarrhoea. Cochrane Database Syst Rev CD004794.

    • PubMed
    • Search Google Scholar
    • Export Citation
  • 12.

    Sinha I, Jones L, Smyth RL, Williamson PR, 2008. A systematic review of studies that aim to determine which outcomes to measure in clinical trials in children. PLoS Med 5: e96.

    • PubMed
    • Search Google Scholar
    • Export Citation
  • 13.

    Black RE, Brown KH, Becker S, Yunus M, 1982. Longitudinal studies of infectious diseases and physical growth of children in rural Bangladesh. I. Patterns of morbidity. Am J Epidemiol 115: 305314.

    • PubMed
    • Search Google Scholar
    • Export Citation
  • 14.

    Koster FT, Palmer DL, Chakraborty J, Jackson T, Curlin GC, 1987. Cellular immune competence and diarrheal morbidity in malnourished Bangladeshi children: a prospective field study. Am J Clin Nutr 46: 115120.

    • PubMed
    • Search Google Scholar
    • Export Citation
  • 15.

    Blum D, Feachem RG, 1983. Measuring the impact of water supply and sanitation investments on diarrhoeal diseases: problems of methodology. Int J Epidemiol 12: 357365.

    • PubMed
    • Search Google Scholar
    • Export Citation
  • 16.

    O’donnell LJD, Virjee J, Heaton K, 1988. Pseudo-diarrhea in the irritable bowel syndrome-patients records of stool form reflect transit-time while stool frequency does not. Gut 29: A1455A1455.

    • PubMed
    • Search Google Scholar
    • Export Citation
  • 17.

    Lewis SJ, Heaton KW, 1997. Stool form scale as a useful guide to intestinal transit time. Scand J Gastroenterol 32: 920924.

  • 18.

    Chumpitazi BP, Lane MM, Czyzewski DI, Weidler EM, Swank PR, Shulman RJ, 2010. Creation and initial evaluation of a stool form scale for children. J Pediatr 157: 594597.

  • 19.

    Aiemjoy K et al. 2016. ‘If an eye is washed properly, it means it would see clearly’: a mixed methods study of face washing knowledge, attitudes, and behaviors in rural Ethiopia. PLoS Negl Trop Dis 10: e0005099.

    • PubMed
    • Search Google Scholar
    • Export Citation
  • 20.

    Aiemjoy K et al. 2016. Is using a latrine “a strange thing to do”? A mixed-methods study of sanitation preference and behaviors in rural Ethiopia. Am J Trop Med Hyg 96: 6573.

    • PubMed
    • Search Google Scholar
    • Export Citation
  • 21.

    Aiemjoy K, Gebresillasie S, Stoller NE, Shiferaw A, Tadesse Z, Chanyalew M, Aragie S, Callahan K, Keenan JD, 2018. Epidemiology of soil-transmitted helminth and intestinal protozoa infections in preschool-aged children in the Amhara region of Ethiopia. Am J Trop Med Hyg 96: 866872.

    • PubMed
    • Search Google Scholar
    • Export Citation
  • 22.

    Lane MM, Czyzewski DI, Chumpitazi BP, Shulman RJ, 2011. Reliability and validity of a modified Bristol stool form scale for children. J Pediatr 159: 437441.e1.

  • 23.

    Morton A, Dobson A, 1989. Assessing agreement. Med J Aust 150: 384387.

  • 24.

    Cohen J, 1968. Weighted kappa: nominal scale agreement provision for scaled disagreement or partial credit. Psychol Bull 70: 213220.

  • 25.

    Rogers W, 1994. Regression standard errors in clustered samples. Stata Tech Bull 3: 1923.

  • 26.

    Genders TSS, Spronk S, Stijnen T, Steyerberg EW, Lesaffre E, Myriam Hunink MG, 2012. Methods for calculating sensitivity and specificity of clustered data: a tutorial. Radiology 265: 910916.

    • PubMed
    • Search Google Scholar
    • Export Citation
  • 27.

    Coughlin SS, Trock B, Criqui MH, Pickle LW, Browner D, Tefft MC, 1992. The logistic modeling of sensitivity, specificity, and predictive value of a diagnostic test. J Clin Epidemiol 45: 17.

    • PubMed
    • Search Google Scholar
    • Export Citation
  • 28.

    Janssens ACJW, Deng Y, Borsboom GJJM, Eijkemans MJC, Habbema JDF, Steyerberg EW, 2005. A new logistic regression approach for the evaluation of diagnostic test results. Med Decis Making 25: 168177.

    • PubMed
    • Search Google Scholar
    • Export Citation
  • 29.

    Baqui AH, Black RE, Yunus MD, Hoque ARA, Chowdhury HR, Sack RB, 1991. Methodological issues in diarrhoeal diseases epidemiology: definition of diarrhoeal episodes. Int J Epidemiol 20: 10571063.

    • PubMed
    • Search Google Scholar
    • Export Citation
  • 30.

    Blake MR, Raker JM, Whelan K, 2016. Validity and reliability of the Bristol stool form scale in healthy adults and patients with diarrhoea-predominant irritable bowel syndrome. Aliment Pharmacol Ther 44: 693703.

    • PubMed
    • Search Google Scholar
    • Export Citation
  • 31.

    Rogan WJ, Gladen B, 1978. Estimating prevalence from the results of a screening test. Am J Epidemiol 107: 7176.

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