Cambridge, MA 

Lexington, MA 

Hadley, MA 

Bethesda, MD 

Chicago, IL 

Abt Associates Inc. 

Suite 800 North 

4550 Montgomery Avenue 

Bethesda, MD 20814-3343 

The Study of 

Thimerosal and 

Autism 

Documentation and 

Codebook for the 

Prenatal 

Ethylmercury 

Exposures File: 

September 3, 2010 

Prepared for 

Frank DeStefano 

National Immunization 

Program 

Centers for Disease Control 

and Prevention 

Atlanta, GA 30329 

Prepared by 

Cristofer Price 

Yeqin He 
This documentation was prepared by Cristofer Price and Yeqin He of Abt Associates Inc. 

for the Immunization Safety Office (ISO) of the Centers for Disease Control and 

Prevention (CDC) Atlanta, GA 30333. Questions about the documentation, substantive 

questions, or technical issues regarding the data file should be directed to the CDC ISO, 

MS D26, 1600 Clifton Road, Atlanta, Georgia 30333 (404-639-8256). 

Suggested Citation for Study of Thimerosal and Autism Public Use Data Set: 

Price, C.S., He, Y. (2010) The Study of Thimerosal and Autism: Data Set 

Documentation. Bethesda MD: Abt Associates, Inc; Prepared for the National 

Immunization Program Centers for Disease Control and Prevention Atlanta, GA 

Abt Associates Inc. 1 
Documentation and Codebook
 

for the
 

Prenatal Ethylmercury Exposures File
 

1. Introduction to the Prenatal Ethylmercury Exposures File..................................... 2
 

2. File Formats and Variable Descriptions................................................................... 3
 

1. Introduction to the Prenatal Ethylmercury Exposures 

File 

The Prenatal Ethylmercury Exposures File contains the data that were used to construct 

the measures of prenatal exposure to ethylmercury from thimerosal-containing vaccines 

and immune globulin preparations received by study children’s mothers during their 

pregnancies with the study children. The Prenatal Ethylmercury Exposures File is 

provided with the public use data in order to make the calculation of exposure amounts 

transparent, and so that analysts have the potential to calculate alternative measures of 

exposure

1

. For a full description of the creation of the measures prenatal exposure to 

ethylmercury from thimerosal-containing vaccines and immune globulin preparations 

received children’s mothers during their pregnancies with the study children, see Section 

7.4 of the Technical Report (Volume 1). 

1 For example, a future analyst might want to create a measure that accounts for the pregnancy trimester 

when thimerosal-containing vaccines or immune globulin preparations were received. Or a future analyst 

might want to do an analysis where records with particular IG decision codes (Technical Report Section 

7.4.3) are omitted from an analyses 

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2. File Formats and Variable Descriptions 

The Prenatal Ethylmercury Exposures File is provided in three formats: 1) ASCII text format, 2) SAS file, and 3) Excel spreadsheet. 

For analysis purposes, the first two formats are recommended. The excel spreadsheet is provided because it is in a convenient format 

for visual inspection of the data. There are 1,095 records in the file. 

Exhibit 1. 

Variables Included in the Prenatal Ethylmercury Exposures File 

Sourcea 

Variable Name Type Label Med. 

Chrt. 

Par. 

Int. Notesb 

Data Management Variables 

ChildID Num ChildID for Merging Data Sets 

Cumulative Exposure Variables 

PreNatThimer Num Cumulative mercury amount during pregnancy X X Exposure variable used in main 

analyses 

PreNatThimer_Alt Num Cumulative mercury amount during pregnancy (alternative) X X Alternative exposure variable. See Vol I, 

Section 7.4.4 and Vol II Section 11. 

Immune Globulin Variables 

DecisionCode_IG Num IG Decision code See Vol. I Section 7.4.3 

PN_IG_MatReport Char Maternal report of IG receipt during pregnancy X In parent interview, mother reported 

having received an immune globulin 

during her pregnancy 

RhStatus Num Mat. Rh blood group 1=rhpos,2=rhNeg,8=Unknown X Maternal Rh blood group status 

d_IGdate1 Num Months from IG receipt #1 to birth of child X Months from receipt of IG to birth of 

child (e.g., 1.8 means that IG was 

received 1.8 months before child was 

born). Negative values indicate receipt 

after child was born (e.g., -0.03 means 

that IG was received 0.03 months after 

delivery). See Vol. I Section 7.4.3 

d_IGdate2 Num Months from IG receipt #2 to birth of child X 

d_IGdate3 Num Months from IG receipt #3 to birth of child X 

PN_IG1_Product Char Type of IG product recieved (IG #1) X Final product type (e.g. Rhogam, 

Micrhogam, Gamulin, Hyproh-d) used to 

determine ethylmercury exposure 

amount See Vol 1. Section 7.4.4 

PN_ProductInfo1 Num =1 if specific info recorded (IG #1) X See Vol 1. Section 7.4.4 

PN_IG1_amt Num Mercury amount in IG #1 See Vol 1. Section 7.4.4 

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Exhibit 1. 

Variables Included in the Prenatal Ethylmercury Exposures File 

Sourcea 

Variable Name Type Label Med. 

Chrt. 

Par. 

Int. Notesb 

PN_IG1_Amt_alt Num Alternate Mercury amount assigned for IG #1 See Vol 1. Section 7.4.4 

Chrt_IG_Prod1 Char Original chart text on IG #1 product X Original text as recorded in med. chart. 

Chrt_IG_Lot1 Char Original chart text on IG #1 lot number X Original text as recorded in med. chart. 

Chrt_IG_Mfr1 Char Original chart text on IG #1 manufacturer X Original text as recorded in med. chart. 

PN_IG2_Product Char Type of IG product recieved (IG #2) X 2nd of up to 3 prenatal IGs received. 

See notes for IG #1. 

PN_ProductInfo2 Num =1 if specific info recorded (IG #2) X 

PN_IG2_amt Num Mercury amount in IG #2 

PN_IG2_Amt_alt Num Alternate Mercury amount assigned for IG #2 

Chrt_IG_Prod2 Char Original chart text on IG #2 product X 

Chrt_IG_Lot2 Char Original chart text on IG #2 lot number X 

Chrt_IG_Mfr2 Char Original chart text on IG #2 manufacturer label X 

PN_IG3_Product Char Type of IG product recieved (IG #3) X 3rd of up to 3 prenatal IGs received. 

See notes for IG #1. 

PN_ProductInfo3 Num =1 if specific info recorded (IG #3) X 

PN_IG3_amt Num Mercury amount in IG #3 

PN_IG3_Amt_alt Num Alternate Mercury amount assigned for IG #3 

Flu Vaccine Variables 

DecisionCode_Flu Num Decision code for prenatal flu receipt See Vol. I Section 7.4.3 

PN_FluRecd Num =1 if flu received during pregnancy, =0 else X X 

PN_FluAmt Num Mercury amount in flu receipt 

PN_Flu_MatReport Char Maternal report of flu receipt X 

PN_Flu_MatWhere Num Maternal report 1=recvd in HMO, 2=outside HMO,8=DK X 

PN_Flu_Chart Num =1 if med chart indicated flu receipt during pregnancy X 

d_fludate Num Months from flu receipt to birth of child X 

Rubella Vaccine Variables 

PN_RubAmt 

PN_RubRecd 

d_rubdate 

Num 

Num 

Num 

Mercury exposure amount from: Rubella 

=1 if recieved during pregnancy: Rubella 

Months from Rubella reciept to birth of child 

X 

X 

See Vol. I Section 7.4.4 

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Exhibit 1. 

Variables Included in the Prenatal Ethylmercury Exposures File 

Sourcea 

Variable Name Type Label Med. 

Chrt. 

Par. 

Int. Notesb 

rubprod 

rubman 

Char 

Char 

Chart text: Rubella product 

Chart text: Rubella manufacturer 

X 

X 

rublot Char Chart text: Rubella lot number X 

Tetanus – diphtheria Vaccine Variables 

PN_TDAmt Num Mercury exposure amount from: TD See Vol. I Section 7.4.4 

PN_TDRecd Num =1 if recieved during pregnancy: TD X 

d_TDdate Num Months from TD reciept to birth of child X 

TDProd Char Chart text: TD product X 

TDman Char Chart text: TD manufacturer X 

TDlot Char Chart text: TD lot number X 

Tetanus Vaccine Variables 

PN_TETAmt Num Mercury exposure amount from: Tetanus See Vol. I Section 7.4.4 

PN_tetrecd Num =1 if recieved during pregnancy: Tetanus X 

d_tetdate Num Months from Tetanus reciept to birth of child X 

tetProd Char Chart text: Tetanus product X 

tetman Char Chart text: Tetanus manufacturer X 

tetlot Char Chart text: Tetanus lot number X 

Hepatitis B Vaccine Variables 

PN_HepBAmt Num Mercury exposure amount from: HepB See Vol. I Section 7.4.4 

PN_HepBrecd Num =1 if recieved during pregnancy: HepB X 

d_hepBdate Num Months from HepB reciept to birth of child X 

hepbProd Char Chart text: HepB product X 

hepbman Char Chart text: HepB manufacturer X 

hepblot Char Chart text: HepB lot number X 

Pneumococcal Vaccine Variables 

PN_PneuAmt 

PN_pneurecd 

d_pneudate 

pneuProd 

pneuman 

Num 

Num 

Num 

Char 

Char 

Mercury exposure amount from: Pneumococcal 

=1 if recieved during pregnancy: Pneumococcal 

Months from Pneumococcal reciept to birth of child 

Chart text: Pneumococcal product 

Chart text: Pneumococcal manufacturer 

X 

X 

X 

X 

See Vol. I Section 7.4.4 

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Exhibit 1. 

Variables Included in the Prenatal Ethylmercury Exposures File 

Sourcea 

Variable Name Type Label Med. 

Chrt. 

Par. 

Int. Notesb 

pneulot Char Chart text: Pneumococcal lot number X 

Meningococcal Vaccine Variables 

PN_MenAmt Num Mercury exposure amount from: Meningococcal See Vol. I Section 7.4.4 

PN_menrecd Num =1 if recieved during pregnancy: Meningococcal X 

d_mendate Num Months from Meningococcal reciept to birth of child X 

menProd Char Chart text: Meningococcal product X 

menman Char Chart text: Meningococcal manufacturer X 

menlot Char Chart text: Meningococcal lot number X 

Rabies Vaccine Variables 

PN_rabAmt Num Mercury exposure amount from: Rabies See Vol. I Section 7.4.4 

PN_rabrecd Num =1 if recieved during pregnancy: Rabies 

d_rabdate Num Months from Rabies reciept to birth of child X 

rabProd Char Chart text: Rabies product X 

rabman Char Chart text: Rabies manufacturer X 

rablot Char Chart text: Rabies lot number X 

Other Vaccine Variables 

PN_OthvAmt Num Mercury exposure amount from: Other Vaccine See Vol. I Section 7.4.4 

PN_othvrecd Num =1 if recieved during pregnancy: Other Vaccine X 

d_othvdate Num Months from Other Vaccine receipt to birth of child X 

othvProd Char Chart text: Other Vaccine product X 

othvman Char Chart text: Other Vaccine manufacturer X 

othvlot Char Chart text: Other Vaccine lot number X a Data Source: Medical chart abstraction, or reported by mother as part of parent interview.
 b Vol I and Vol II and section numbers correspond to Technical Reports Volumes I and II (Price et al, 2009), which are included with this data set.
 

Abt Associates Inc. 6