CHS CERTIFIED HISTOCOMPATIBILITY
SPECIALIST FINAL PAPER 2026 200
QUESTIONS WITH VERIFIED CORRECT
ANSWERS ELITE STUDY GUIDE FULL
SOLUTION GRADED A+
⩥ Which of the following statements is FALSE?
a. Significant R values increase as N increases
b. Significant Chi-Square values increase as N increases
c. Chi-square values have a wider numerical range than R values
d. R values can be derived directly from Chi-square without access to
the raw data. Answer: a. Significant R values increase as N increases
⩥ Which of the below equivalencies is FALSE?
a. B*3501 = B35
b. B*1501 = B77
c. B*1522 = B*3543
d. B*5002 = B45. Answer: b. B*1501 = B77
⩥ Which is false regarding the chi-square statistic?
,a. The Yates correction should be used, especially with small sample
sizes
b. Use of chi-square is an example of an inferential statistical method
c. The chi-square should only be used when the data is expressed as
TN,TP,FN, and FP
d. Chi-square becomes unreliable when expected values become small.
Answer: c. The chi-square should only be used when the data is
expressed as TN,TP,FN, and FP
⩥ How can granulocytes in the cell preparation interfere with a
crossmatch assay?
a. They take up staining dyes resulting in false positive results
b. They kill lymphocytes resulting in false positive results
c. Since live granulocytes do not take up AO they dilute the count of live
cells
d. Since dead granulocytes do not take up EB they dilute the count of
dead cells. Answer: a. They take up staining dyes resulting in false
positive results
⩥ Within the field of histocompatibility, Prozone is a term that refers
to...
,a. Complete cell death during a crossmatch due to excess antibody
b. Complete cell death during a crossmatch due to excess complement
c. Achieving the correct titer of AHG to avoid false reactions during an
AHG-CDC assay
d. False negative crossmatch results due to excess antibody. Answer: d.
False negative crossmatch results due to excess antibody
⩥ AHG best enhances the detection of anti-HLA antibodies under the
following circumstances during a crossmatch assay?
a. Low titer or IgM antibody
b. Low titer or IgG4 antibody
c. CYNAP or IgM antibody
d. Low titer or high-complement binding antibodies. Answer: b. Low
titer or IgG4 antibody
⩥ Formamide and TMAC can be used in what assay for what purpose?
a. PCR-SSP: To raise the annealing temperature
b. AHG-CDC: To fix the cells
c. PCR-SSP: To increase yield
d. SSOP: To enhance annealing specificity. Answer: d. SSOP: To
enhance annealing specificity
, ⩥ The human haploid genome is 3.3x109 base pairs. Assuming a
random distribution of bases, what size probe would be expected to have
a single target in the haploid genome?
a. 6bp
b. 10bp
c. 16bp
d. 26bp. Answer: c. 16bp
⩥ What are the most probable haplotype assignments for the displayed
family?
HLA-A HLA-B HLA-DR
Patient *29 *07 *0404
*31 *40 *1501
Sibling #1 29,31 7,60 *0404
*1501
Sibling #2 11,29 7,60 13,15
SPECIALIST FINAL PAPER 2026 200
QUESTIONS WITH VERIFIED CORRECT
ANSWERS ELITE STUDY GUIDE FULL
SOLUTION GRADED A+
⩥ Which of the following statements is FALSE?
a. Significant R values increase as N increases
b. Significant Chi-Square values increase as N increases
c. Chi-square values have a wider numerical range than R values
d. R values can be derived directly from Chi-square without access to
the raw data. Answer: a. Significant R values increase as N increases
⩥ Which of the below equivalencies is FALSE?
a. B*3501 = B35
b. B*1501 = B77
c. B*1522 = B*3543
d. B*5002 = B45. Answer: b. B*1501 = B77
⩥ Which is false regarding the chi-square statistic?
,a. The Yates correction should be used, especially with small sample
sizes
b. Use of chi-square is an example of an inferential statistical method
c. The chi-square should only be used when the data is expressed as
TN,TP,FN, and FP
d. Chi-square becomes unreliable when expected values become small.
Answer: c. The chi-square should only be used when the data is
expressed as TN,TP,FN, and FP
⩥ How can granulocytes in the cell preparation interfere with a
crossmatch assay?
a. They take up staining dyes resulting in false positive results
b. They kill lymphocytes resulting in false positive results
c. Since live granulocytes do not take up AO they dilute the count of live
cells
d. Since dead granulocytes do not take up EB they dilute the count of
dead cells. Answer: a. They take up staining dyes resulting in false
positive results
⩥ Within the field of histocompatibility, Prozone is a term that refers
to...
,a. Complete cell death during a crossmatch due to excess antibody
b. Complete cell death during a crossmatch due to excess complement
c. Achieving the correct titer of AHG to avoid false reactions during an
AHG-CDC assay
d. False negative crossmatch results due to excess antibody. Answer: d.
False negative crossmatch results due to excess antibody
⩥ AHG best enhances the detection of anti-HLA antibodies under the
following circumstances during a crossmatch assay?
a. Low titer or IgM antibody
b. Low titer or IgG4 antibody
c. CYNAP or IgM antibody
d. Low titer or high-complement binding antibodies. Answer: b. Low
titer or IgG4 antibody
⩥ Formamide and TMAC can be used in what assay for what purpose?
a. PCR-SSP: To raise the annealing temperature
b. AHG-CDC: To fix the cells
c. PCR-SSP: To increase yield
d. SSOP: To enhance annealing specificity. Answer: d. SSOP: To
enhance annealing specificity
, ⩥ The human haploid genome is 3.3x109 base pairs. Assuming a
random distribution of bases, what size probe would be expected to have
a single target in the haploid genome?
a. 6bp
b. 10bp
c. 16bp
d. 26bp. Answer: c. 16bp
⩥ What are the most probable haplotype assignments for the displayed
family?
HLA-A HLA-B HLA-DR
Patient *29 *07 *0404
*31 *40 *1501
Sibling #1 29,31 7,60 *0404
*1501
Sibling #2 11,29 7,60 13,15
