Evaluation of Hemoglobin Measurement Tools for Child Anemia Screening in Rwanda
Condition: Anemia
MeSH terms: Anemia
Study type: Observational

Summary: 
      The purpose of this study is to evaluate the use of a noninvasive Hb device (Pronto® with
      DCI-mini™ sensors) as an accurate method for measuring Hb levels among children between 6 and
      59 months against the standard reference hematology analyzer. The secondary purpose is to
      evaluate the accuracy of two HemoCue® Hb 201+ capillary blood collection methods against the
      standard reference hematology analyzer.

      The study hypothesizes that the Pronto® with DCI-mini™ sensor will approximate Hb values
      within ±1.0 g/dL and secondly, it will correctly classify participants as anemic or not
      anemic with less than 31% disagreement when compared to the standard reference hematology
      analyzer among children 6 to 59 months of age. Additionally, the two different HemoCue® Hb
      201+ capillary blood collection methodologies will both approximate Hb values within ±1.0
      g/dL and secondly, it will correctly classify participants as anemic or not anemic with less
      than 35% disagreement when compared to the standard reference hematology analyzer among
      children 6 to 59 months of age.
    

Detailed description: 
      The Hb values of 132 children, between 6 and 59 months of age will be obtained, using three
      different Hb assessment methods during the same assessment visit for comparison with the
      standard reference hematology analyzer(Sysmex KN21) results.

      The purpose of the research is: 1) To evaluate the accuracy of the noninvasive Masmio Pronto®
      device with DCI-mini sensor in measuring Hb when compared to measuring Hb using the standard
      reference hematology analyzer, and 2) To evaluate the accuracy of both the HemoCue® Hb 201+
      gravity and wicking methodologies of capillary blood collection against the standard
      reference hematology analyzer.

      To validate and determine the accuracy of the Pronto® with DCI-mini™ sensor, the 132 Pronto®
      Hb values will be compared to the Hb values obtained by the standard reference hematology
      analyzer to determine if the overall average difference between measurements does not exceed
      1.0g/dL.

      To validate and determine the accuracy of each of the two HemoCue® 201+ blood collection
      methods, 50% of the children will have their Hb measured using the wicking method and 50%
      will have their Hb measured using the gravity method. The Hb values obtained by the two
      different HemoCue® 201+ blood collection methods will be compared to the standard reference
      hematology analyzer to determine if the overall average difference between each method and
      the standard reference is within 1.0g/dL.

      For each child, study nurse/coordinator will: collect health information from the child,
      categorize skin pigmentation using the Massey and Martin NIS Skin Color Scale, measure and
      record finger diameter using the Masimo finger measuring tool (if none of the fingers are the
      appropriate size for the sensor, then the big toe will be measured and used instead).
      Capillary blood samples of the children will be taken via finger pricking of the third or
      fourth digit. If a child of 6-11 months is acutely malnourished (as determined by their
      weight-for-height Z score), the blood drop will be obtained from their heel in accordance
      with Hemocue® 201+ protocol and to ensure the finger bone is not injured due to insufficient
      finger padding. For both blood sampling locations, the first two drops of blood will be wiped
      away and only the third blood drop will be used. The randomization process and the data
      analysis phase will not be blinded.

      To determine the accuracy of the noninvasive device, the difference between Hb values
      obtained from the Pronto® with DCI-mini™ sensory and standard reference hematology analyzer
      (Sysmex KN21™) will be calculated for each child and an average obtained. In addition to the
      mean difference (bias), the standard deviation, 95% confidence interval, range, and limits of
      agreement will also be obtained. Accuracy of Hb measurement by the noninvasive device will be
      assessed by determining whether the measurement obtained with each noninvasive device falls
      within ±1.0 g/dL of the standard reference. With 100 samples and assuming the correlation
      between measurement methods is at least 0.93, we have 97-99% power to confirm that the
      average difference between the two Hb measurement methods does not exceed 1.0 g/dL. This
      analysis will be conducted using a paired t-test since we will be testing a limit on the
      difference between the measures. The prevalence rate of anemia will also be estimated for the
      group from the noninvasive measurements in comparison to the standard reference measurements
      and analyzed by paired t-test. For this comparison, our sample size of 100 affords us enough
      power to determine if participants are correctly classified as anemic or not anemic, with
      less than 31% disagreement.

      A similar process will be followed for each of the two HemoCue® Hb 201+ capillary blood
      collection methodologies in comparison to the standard reference hematology analyzer using a
      paired t-test to test the limit on the difference between measures. With 50 samples and
      assuming the correlation between measurement methods is at least 0.93, we again have 77-99%
      power to confirm that the average difference between each of the two Hb measurement methods
      and the standard reference does not exceed 1.0 g/dL. The prevalence rate of anemia will also
      be estimated for each of the HemoCue® 201+ study arms for comparison with the standard
      reference measurements and analyzed by paired t-test. For this comparison, our sample size of
      100 enables us to test if participants are correctly classified as anemic or not anemic, with
      less than 35% disagreement.
    

Observational model: Case-Only
Time perspective: Cross-Sectional
Sampling method: Probability Sample
Study population: 
        Participants will be children 6 to 59 months of age, receiving outpatient care from Centre
        Hospitalier Universitaire de Kigali (CHUK) and providing a venous blood sample for their
        health care.
      
Keywords: Anemia; Iron deficiency; noninvasive anemia screening