Comparison of the NBM 200 non-invasive haemoglobin sensor with Sahli’s hemometer among adolescent girls in rural India

Ahankari, Anand S.; Dixit, J.V.; Fogarty, Andrew W.; Tata, Laila J.; Myles, Puja R.

Abstract

Objective: The study objective was to compare haemoglobin measurements between the NBM 200 (non-invasive haemoglobin sensor) and Sahli’s hemometer in adolescent girls in a rural Indian setting.

Methods: Participants included girls aged between 13 to 17 years from 34 villages in Tuljapur and Lohara blocks of Osmanabad district, Maharashtra, India. Haemoglobin (Hb) measurements from the non-invasive sensor (NBM 200) were compared with measurements obtained from Sahli’s hemometer using Bland-Altman plot, Spearman correlation coefficient, sensitivity, specificity, and area under the receiver operating characteristic curve analysis (AUROC).

Results: Paired measurements from both methods were obtained from 766 adolescent girls (N=766). Haemoglobin levels estimated by Sahli’s hemometer ranged from 5.0 g/dL to 14.0 g/dL (mean: 10.1 g/dL, standard deviation (SD): 1.41), whereas measurements obtained from the NBM 200 ranged from 9.5 g/dL to 15.2 g/dL (mean: 12.8 g/dL, SD: 1.42). The Bland-Altman analysis indicated a mean difference of -2.70 g/dL (95% Confidence Intervals: -2.84 to -2.55) demonstrating an overestimation of Hb measurement by the NBM 200 compared to the Sahli’s hemometer measurements. The NBM 200 showed low sensitivity (23.6%) and moderate specificity (61.8%) for the diagnosis of anaemia. The AUROC score was 0.43 indicating an underestimation of anaemia in our study population by the NBM 200.

Conclusion: Haemoglobin measurements obtained from the NBM 200 were consistently higher leading to an underestimation of anaemia prevalence compared with Sahli’s hemometer estimates among adolescent girls in India.

Citation

Ahankari, A. S., Dixit, J., Fogarty, A. W., Tata, L. J., & Myles, P. R. (2016). Comparison of the NBM 200 non-invasive haemoglobin sensor with Sahli’s hemometer among adolescent girls in rural India. BMJ Innovations, 2, https://doi.org/10.1136/bmjinnov-2016-000139

• Journal Article Type: Article
• Acceptance Date: Jul 28, 2016
• Online Publication Date: Dec 8, 2016
• Publication Date: Oct 1, 2016
• Deposit Date: Aug 1, 2016
• Publicly Available Date: Oct 1, 2016
• Journal: BMJ Innovations
• Electronic ISSN: 2055-642X
• Publisher: BMJ Publishing Group
• Peer Reviewed: Peer Reviewed
• Volume: 2
• DOI: https://doi.org/10.1136/bmjinnov-2016-000139
• Keywords: Adolescent, Sahli’s hemometer, Anaemia, Non-invasive Haemoglobin, NBM 200, India
• Public URL: https://nottingham-repository.worktribe.com/output/807732
• Publisher URL: http://innovations.bmj.com/content/2/4/144