Mandy, Francis, Nicholson, J. K. A.,  McDougal, J. S.and Cross, G. D.,  Guidelines for Performing Single Platform Absolute CD4+ T-Cell Determinations with CD45 Gating in Persons Infected with Human Immunodeficiency Virus (HIV). MMWR.Morbidity and Mortality Weekly Report Vol. 52 RR-2, 1-13. 1-31-2003.

Schalla, W. O. and et al. Notice to Readers: Approval of a New Rapid Test for HIV Antibody. MMWR.Morbidity and Mortality Weekly Report vol. 51 No 46, 1-3. 11-22-2002.

Hofherr LK, Francis DP, Astles JR, Schalla WO: HIV-1 Antiretroviral Resistance Testing Laboratories. Clin Lab Sci 2002;15:213-219.

Schalla WO, et al: CDC Guidelines for Reporting HIV Laboratory Test Results. Lab Med 2002;33:2-6.

Francis DP, Peddecord KM, Hofherr LK, Astles JR, Schalla WO: Viral Load Test Reports. Arch Pathol Lab Med 2001;125:1546-1554.

Schalla, W. O., Schulte, Joann, and et al. Guidelines for Laboratory Test Result Reporting of Human Immunodeficiency Virus Type 1 Ribonucleic Acid Determination. MMWR.Morbidity and Mortality Weekly Report Vol. 50 RR-20, 1-12. 11-16-2001.

Cross, G.D., J.H. Handsfield, W.O. Schalla. 2000. Extreme Values Reported for Cd4 Absolute Cell Counts by Laboratories Using Dual-Platform Methods: Results From a Performance Evaluation Program. Cytometry 42(6):314

Williams LO, Blumer SO, Schalla WO, et al: Laboratory Performance in Human T-Lymphotrophic Virus Types I/II (HTLV) Analysis. Transfusion 2000;40:1514-1521.

Cross, G.D., J.H. Handsfield, W.O. Schalla. 1999. CD4 T-Cell Enumeration: Single-Platform Methods May Yield More Reproducible Results Than Multi-Platform Methods. Cytometry 38(6): 327.

Francis DP, Peddecord KM, Hofherr LK, Benenson AS, Schalla WO: T-Lymphocyte Immunophenotyping Blind Proficiency Testing: A Model System for CD4+ T-Cells. Clin Lab Sci 1999;12:278-289.

Summary Of The Centers for Disease Control Human Immunodeficiency Virus (HIV) Performance Evaluation Surveys For 1985 and 1986. 1988. R.N. Taylor and V.A. Przybyszewski. Amer. J. Clin. Path. 89:1-13.

Current Trends Update: Serologic Testing For Antibody To Human Immunodeficiency Virus. 1988. Centers for Disease Control. Morbid. Mortal. Weekly Rep. Vol 36 No. 52, 833-845. 01-08-1988.  (Prepared by C.W. Griffin, T.L. Hearn, W.O. Schalla, and R.N. Taylor.)

Sindrome da immunodeficienza acquisita. Valutazione della efficienza die laboratori nella ricerca degli anticorpi HIV. Sommario dei rilevarmenti esguiti dai Centri per il controllo della malattia. 1988. R.N. Taylor and V.A. Przybyszewski. Amer. J. Clin. Path. (Italian edition) 1:9-22.

Model Performance Evaluation Program (HIV Testing): Program Overview. 1988. C.W. Griffin. Infect. Control and Hosp. Epidemiol. 9:364.

Serological Diagnosis Of Immunodeficiency Virus Infection By Western Blot Testing. Aug. 5, 1988. Consortium for Retrovirus Serology Standardization. J. Amer. Med. Assoc. 260:674-679.

Role Of The Centers for Disease Control In Monitoring The Quality Of Laboratory Testing For Human Immunodeficiency Virus Infection. Oct. 15, 1988. W.O. Schalla, T.L. Hearn, C.W. Griffin, and R.N. Taylor. Clin. Microbiol. Newsletter 10:156-159.

Current Trends Problems Created By Heat-Inactivation of Serum Specimens Before HIV-1 Antibody Testing. 1989. Centers for Disease Control. Morbid. Mortal. Weekly Rep. 38:407-413. (Prepared by R.O. Valdiserri, T.L. Hearn, W.O. Schalla, S.O. Blumer, R.N. Taylor). 

Interpretation and Use of Western Blot Assay For Serodiagnosis of HIV-1 Infections: ASTPHLD and CDC Recommendations. 7-21-1989. Centers for Disease Control. (T.L. Hearn and W.O. Schalla). Morbid. Mortal. Weekly Rep. 38:(S-7) 1-7.

Results from CDC's Model Performance Evaluation Program Presented at the Fifth International Conference on AIDS. June 1989. T.L. Hearn, W.O. Schalla, and R.N. Taylor. ASTPHLD Newsletter.

Performance Evaluation Program for Human T-Lymphotropic Virus Type I Antibody Testing Being Implemented by CDC. June 1989. T.L. Hearn, W.O. Schalla, and R.N. Taylor. ASTPHLD Newsletter.

Indirect Immunofluorescence Test Performance and Questionnaire Results From The Centers For Disease Control Model Performance Evaluation Program For Human Immunodeficiency Virus Type 1 Testing. 1990. R.N. Taylor, T.L. Hearn, W.O. Schalla and R.O. Valdiserri. J. Clin. Micro. 28:1799-1807.

Centers For Disease Control Perspective On Quality Assurance For Human Immunodeficiency Virus Type 1 Antibody Testing. 1990. R.O. Valdiserri, R.N. Taylor, T.L. Hearn, W.O. Schalla and H.W. Muir. Arch. Pathol. Lab. Med. 114:263-267.

The Centers For Disease Control's Model Performance Evaluation Program: Assessment Of The Quality of Laboratory Testing For Human Immunodeficiency Virus Type 1 (HIV-1) Infection. 1990. W.O. Schalla, T.L. Hearn, R.N. Taylor, E. Eavenson, R.O. Valdiserri. [Collaborative article with Family of SeroSurveys]. Public Health Reports 105(2):167-71.

MPEP Performance Bulletin No. 1. Indeterminate Western Blot Results On Human T-Lymphotropic Virus Type I/II (HTLV-I/II) Antibody-Positive Samples. Feb. 26, 1990. CDC Model Performance Evaluation Program. (Prepared by S.O. Blumer and W.O. Schalla.)

MPEP Performance Bulletin No. 2. Laboratory Reports and Reporting the Results of Human Immunodeficiency Virus Type 1 (HIV-1) Testing. May 10, 1990. CDC Model Performance Evaluation Program. (Prepared by S.O Blumer, G.D. Cross, and W.O. Schalla.)

Accuracy of Western Blot Testing For Human Immunodeficiency Virus Type 1 (HIV-1) Infection. 1990. W.O. Schalla, G.D. Cross, T.L. Hearn, S.O. Blumer, R.N. Taylor, and R.O. Valdiserri. (Publication of Abstracts for the 1990 American Society for Microbiology Annual Meeting, May 13-17, 1990, Anaheim, California.)

Update: Serologic Testing For HIV-1 Antibody - United States, 1988 and 1989. June 8, 1990. Centers for Disease Control. Morbid. Mortal. Weekly Rep. 39 No. 22:380-383. (Prepared by A.R. Gerber, W.O. Schalla, and T.L. Hearn.)

Human Immunodeficiency Virus Type-1 (HIV-1) Antibody Testing: Accuracy of Western Blot Results. 1990. W.O. Schalla, T.L. Hearn, G.D. Cross, S.O. Blumer, R.N. Taylor, and R.O. Valdiserri. (Publication of Abstracts for the Sixth International AIDS Conference, June 20-24, 1990, San Francisco, California.)

Analytic Sensitivity And Specificity Of Enzyme Immunoassay Results In Testing For Human Immunodeficiency Virus Type 1 (HIV-1) Antibody. 1990. G.D. Cross, W.O. Schalla, T.L. Hearn, S.O. Blumer, R.N. Taylor, and R.O. Valdiserri. (Publication of Abstracts for the Sixth International AIDS Conference, June 20-24, 1990, San Francisco, California.)

Assessment Of Human T-Cell Lymphotrophic Virus Type I/II Antibody Testing. 1990. S.O. Blumer, T.L. Hearn, W.O. Schalla, G.D. Cross, and R.O. Valdiserri. (Publication of Abstracts for the Sixth International AIDS Conference, June 20-24, 1990, San Francisco, California.)

Association of Performance On EIA for HIV-1 Antibody With Laboratory Characteristics And Testing Practices. 1990. A.R. Gerber, C.A. Johnson, R.E. Schwartz, T.L. Hearn, and R.O. Valdiserri. (Publication of Abstracts for the Sixth International AIDS Conference, June 20-24, 1990, San Francisco, California.)

Reporting The Results Of Human Immunodeficiency Virus Testing. Dec. 22/29, 1990. A.S. Benenson, K.M. Peddecord, L.K. Hofherr, M.S. Ascher, R.N. Taylor, and T.L. Hearn. J. Amer. Med. Assoc. 262:3435-3438.

Quality Of Laboratory Performance In Testing for HIV-1 Antibody: Variables Associated in Multivariate Analyses. 1991. A.R. Gerber, R.O. Valdiserri, C.A. Johnson, R.E. Schwartz, J.S. Hancock, and T.L. Hearn. Arch. Pathol. Lab. Med. 115:1091-1096.

Capacity of U.S. Labs To Provide TLI In Support of Early HIV-1 Intervention. 1991. R.O. Valdiserri, G.D. Cross, A.R. Gerber, R.E. Schwartz, and T.L. Hearn. Amer. J. Public Health 81:491-494.

MPEP Performance Bulletin No. 3. Interpretation Criteria Used For Reporting Results of Human Immunodeficiency Virus Type 1 (HIV-1) Western Blot Tests. Feb. 5, 1991. CDC Model Performance Evaluation Program. (Prepared by G.D. Cross, W.O. Schalla, and S.O. Blumer.)

Assessment of Human T-lymphotropic Virus Types I and II Antibody Testing. 1991. S.O. Blumer, W.O. Schalla, G.D. Cross, T.L. Hearn, D.A. Howerton, and R.O. Valdiserri. (Publication of Abstracts, American Society for Microbiology, May 1991, Dallas, Texas.)

Human Immunodeficiency Virus Type 1 (HIV-1) Antibody Testing: Analytic Sensitivity and Analytic Specificity of Enzyme Immunoassay (EIA) Results. 1991. G.D. Cross, W.O. Schalla, S.O. Blumer, T.L. Hearn, and R.O. Valdiserri. (Publication of Abstracts, American Society for Microbiology, May 1991, Dallas, Texas.)

Analysis of Indeterminate Human T-lymphotropic Virus Type I (HTLV-I) Western Blot Interpretations Reported for HTLV-Type II Infected Individuals. 1991. S.O. Blumer, W.O. Schalla, G.D. Cross, J.S. Hancock, H.W. Muir, and T.L. Hearn. (Publication of Abstracts, VII International Conference on AIDS, Florence, Italy, June 16-21, 1991.)

Evaluation of Laboratory Performance of T-Lymphocyte Immunophenotyping In Support of Early HIV-1 Intervention and Prevention. 1991. A.R. Gerber, G.D. Cross, W.O. Schalla, J.S. Hancock, H.W. Muir, T.L. Hearn, and R.O. Valdiserri. (Publication of Abstracts, VII International Conference on AIDS, Florence, Italy, June 16-21, 1991.)

Analytic Specificities and Sensitivities of Indirect Immunofluorescence Results In Testing for Human Immunodeficiency Virus Type 1 (HIV-1) Antibody From 1988 to 1990. 1991. R.N. Taylor, G.D. Cross, S.O. Blumer, A.R. Gerber, W.O. Schalla, and T.L. Hearn. (Publication of Abstracts, VII International Conference on AIDS, Florence, Italy, June 16-21, 1991.)

Update On Western Blot Testing: Performance Evaluation of Laboratories That Test For Human Immunodeficiency Virus Type 1 (HIV-1) Antibodies. 1991. W.O. Schalla, G.D. Cross, S.O. Blumer, J.S. Hancock, A.R. Gerber, H.W. Muir, and T.L. Hearn. (Publication of Abstracts, VII International Conference on AIDS, Florence, Italy, June 16-21, 1991.)

Analytic Sensitivity and Specificity of Enzyme Immunoassay Results In Testing For Human Immunodeficiency Virus Type 1 (HIV-1) Antibody. 1991. G.D. Cross, W.O. Schalla, S.O. Blumer, R.N. Taylor, A.R. Gerber, T.L. Hearn, and R.O. Valdiserri. (Publication of Abstracts, VII International Conference on AIDS, Florence, Italy, June 16-21, 1991.)

Correlation Between Laboratory Personnel Parameters and The Quality of HIV-1 Antibody Testing In U.S. Laboratories. 1991. T.L. Hearn, R.O. Valdiserri, C.A. Johnson, J.S. Hancock, R.E. Schwartz, and A.R. Gerber. (Publication of Abstracts, VII International Conference on AIDS, Florence, Italy, June 16-21, 1991.)

Information About AIDS. July 15, 1991. R.N. Taylor. Annals of Internal Medicine 115(2):160.

Interpretive Criteria Used To Report Western Blot Results for HIV-1-Antibody Testing - United States. Oct. 11, 1991. Centers for Disease Control. Morbid. Mortal. Weekly Rep. Vol. 40 No. 40:692-695. (Prepared by S.O. Blumer, W.O. Schalla, and G.D. Cross.) 

Content and Design of Laboratory Report Forms For Human Immunodeficiency Virus Type 1 Antibody Testing. 1992. D.J. Hewitt, K.M. Peddecord, D.P. Francis, A.S. Benenson, L.K. Hofherr, K.L. Ferran, R.S. Garfein, and A.R. Gerber. Amer. J. Clin. Path. 98:199-204.

Methods for a Blind Proficiency Testing System. 1992. L.K. Hofherr, K.M. Peddecord, A.S. Benenson, R.S. Garfein, D.P. Francis, K.L. Ferran, and R.N. Taylor. Clin. Lab Sci. 5:160-164. 

Analytic Results of Human Immunodeficiency Virus Type 1 Testing Using Blind Proficiency Testing. 1992. K.M. Peddecord, A.S. Benenson, L.K. Hofherr, R.S. Garfein, D.P. Francis, R.N. Taylor, W.O. Schalla, and M.S. Ascher. Clin. Lab. Sci. 5:165-171. 

Identification of Non-analytic Issues In Human Immunodeficiency Virus Type 1 Antibody Testing Using Blind Proficiency Testing. 1992. K.M. Peddecord, A.S. Benenson, L.K. Hofherr, R.S. Garfein, D.P. Francis, D.J. Hewitt, K.L. Ferran, W.O. Schalla, and T.L. Hearn. Clin. Lab. Sci. 5:172-176. 

Analytic Sensitivity and Specificity of Enzyme Immunoassay Results In Testing For Human Immunodeficiency Virus Type-1 (HIV-1) Antibody. 1992. G.D. Cross, W.O. Schalla, J.S. Hancock, T.L. Hearn, S.O. Blumer, R.N. Taylor, and R.O. Valdiserri. Arch. Pathol. Lab. Med. 116:477-481. 

Use Of A Modified Nominal Group Process For Improving Laboratory Performance in Human Immunodeficiency Virus Type 1 Antibody Testing. 1992. D.P. Francis, K.M. Peddecord, D.J. Hewitt, L.K. Hofherr, K.L. Ferran, R.S. Garfein, W.O. Schalla, and R.N. Taylor. Clin. Lab. Management Review. 6:537-538, 543-546.

From the CDC: The Laboratory Performance Information Exchange System. January, 1992. Roger N. Taylor. Medical Laboratory Organizer. 

Human T-Lymphotropic Virus Type I/II. Status of Enzyme Immunoassay and Western Blot Testing in the United States in 1989 and 1990. May, 1992. S.O. Blumer, T.L. Hearn, W.O. Schalla, G.D. Cross, R.O. Valdiserri. Arch. Pathol. Lab. Med. 116:471-476. 

Guidelines for the Performance of CD4+ T-Cell Determinations in Persons with Human Immunodeficiency Virus Infection. May, 1992. Centers for Disease Control. Morbid. Mortal. Weekly Rep. 41:No. RR-8.001 

Availability of Flow Cytometric Immunophenotyping of Lymphocytes to Hospital Patients - United States, 1990. Aug. 21, 1992. Morbid. Mortal Weekly Rep. 41(33):608-610. (Prepared by Div. HIV/AIDS, W.O. Schalla, and G.D. Cross.) 

Sources of Influence In Changing Policies and Procedures For HIV-1 Testing. 1993. K.M. Peddecord, L.K. Hofherr, A.S. Benenson, K.L. Ferran, Z. Li, R.S. Garfein, D.P. Francis, R.N. Taylor, and W.O. Schalla. Clin. Lab. Sci. 6:359-365. 

Variability of Reporting and Lack of Adherence To Consensus Guidelines In Human T-Lymphocyte Immunophenotyping Reports: Results of a Case Series. 1993. K.M. Peddecord, A.S. Benenson, L.K. Hofherr, D.P. Francis, R.S. Garfein, G.D. Cross, and W.O. Schalla. JAIDS 6:823-830. 

Quality of Laboratory Performance in Testing for HIV-1 Antibody: Identification of Variables Associated With Laboratory Performance. 1993. J.S. Hancock, R.N. Taylor, C.A. Johnson, A.R. Gerber, and W.O. Schalla. Arch. Pathol. Lab. Med. 117:1148-1155. 

Revised Guidelines For The Performance of CD4+ T-Cell Determinations in Persons With Human Immunodeficiency Virus (HIV) Infection. Morbid. Mortal. Weekly Report 3-4-1994;43,No. RR-3. 

Precision of Absolute CD4 Counts Between Laboratories: Results of a Pilot Study. 1995. G.D. Cross, W.O. Schalla, R.N. Taylor, M.T. Siragusa, R.D. Cohn, E.E. Gaunt, and the CD4 PT/A Project Expert Panel. Communications in Clinical Cytometry 22(4). 

Centers for Disease Control and Prevention. Performance Evaluation Programs for Determining HIV-1 Viral Load, Testing for HIV p24 Antigen, and Identifying Mycobacterium tuberculosis Using Nucleic Acid Amplification Tests. Morbidity Mortality Weekly Report (MMWR),  02-21-1997.  46: No. 7, 155-156.

Quality Assurance Activities in the Latin Americas and the Caribbean. December 1997.J.R. Cruz, W.O. Schalla, S.A. Larsen. Medical Laboratory Observer Vol. 29;No.7:40-43.  

Nicholson, J. K. A., Hearn, T. L., Cross, G. D., and White, M. D.  1997 Revised Guidelines For The Performance of CD4+ T-Cell Determinations In Persons Infected With Human Immunodeficiency Virus (HIV). Morbid. Mortal. Weekly Report 1-10-1997;46,No. RR2. 

Impact Of Quality Control On Accuracy in HIV Enzyme Immunoassay Testing. J.R.Astles, H.B. Lipman, W.O. Schalla, S.O. Blumer, T.L. Hearn. 1998. Archives Path. Lab. Med. 1998;122(8):700-707. 

Assessment of the Impact of a CD+ T-Cell Testing Laboratory Improvement Program. E. Rosner, M.T. Siragusa, W.O. Schalla, G.D. Cross, R.D. Cohn, and T.L. Hearn. 1998 Archives Path. Lab. Med. 1998;122(6):512-519. 

T-Lymphocyte Immunophenotyping Blind Proficiency Testing: A Model System. 1998. D.P. Francis, K.M. Peddecord, L.K. Hofherr, A.S. Benenson, R.N. Taylor, and W.O. Schalla. Clin. Lab. Science (accepted for publication - December 1998). 

T-Lymphocyte Immunophenotyping in the United States: Practices of Laboratories Enrolled In a Performance Evaluation Program. W.O. Schalla, G.D. Cross, R.N. Taylor, R.L. Jordan, and T.L. Hearn. A monograph developed at CDC - In Press. 

HIV-1 Antibody Testing in the United States: Practices of Laboratories Enrolled In a Performance Evaluation Program. W.O. Schalla, S.O. Blumer, R.N. Taylor, R.L. Jordan, T.L. and Hearn. A monograph developed at CDC - In Preparation. 

The Source of Variability in the CD4+ Count: Results of a Blind Proficiency Series. S.D. Perry, A.S. Benenson, D.P. Francis, K.M. Peddecord, L.K. Hofherr, R.N. Taylor, and W.O. Schalla. 1998. J. Diagnostic and Clinical Laboratory Immunology (submitted for publication).  

Laboratory Performance In Human T-Lymphotropic Virus Types I/II (HTLV-I/II) Analyses. L.W. Williams, S.O. Blumer, W.O. Schalla, P.H. Robinson, J.H. Hansfield, R.J. Fehd, J.H. Hancock, H.B. Lipman, and T.L. Hearn. 1998. J. Clin. Micro. (Submitted for publication).