4.1 Age

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The data set includes the respondent’s date of birth and age as of the initial survey year.  The initial survey year age variable was provided by the Census Bureau based on information collected during the 1966 household screening.  As age inconsistencies were discovered, Census made date of birth information available in the late 1970s.  For the most part, the date of birth and age variables were collected during fielding of the “Household Roster” (HHR) section of the questionnaire.

Date of birth variables (e.g., ‘Day of R’s Birth,’ ‘Month of R’s Birth,’ and ‘Year of R’s Birth’) are provided for the 1968, 1977, 1978, 1982, 1988, and 1991 survey years.  During the 1995–2001 surveys, the respondent was asked to confirm or correct the most recent birth date information available.  A series of variables including age as reported during the screening interview (‘Age, 68’) and ‘Revised Age of R’ at interview date (1968–75 survey years) was also created.  These revised variables are considered to be more accurate than the age information originally reported. 

Table 4.1.1 provides reference numbers for date of birth and age variables; Table 4.1.2 presents age distributions for the Young Women.  Data for reported age and birth dates include a small number of inconsistencies.  As a result, attempts to restrict the universe according to age-related variables may lead to unwanted or incorrect results.  The User Notes below discuss some of the idiosyncratic aspects of these variables.

Table 4.1.1 Reference Numbers for Date of Birth & Age Variables

Year

Date of Birth of R

Age of R

Revised Age of R at Interview Date

Year

Date of Birth of R

Age of R

1968

R00420.10-R00420.12

R00031.

R00420.50

1978

R06491.-R06493.

--

1969

--

--

R01166.50

1982

R07668.-R07670.

R07671.

1970

--

--

R01970.00

1988

R11841.-R11843.

--

1971

--

--

R03119.50

1991

R13133.-R13135.

R13136.

1972

--

--

R03962.50

1995

R16067.-R16070.

R16671.

1973

--

--

R04805.50

1997

R35040.-R35043.

R35044.

1975

--

--

R05345.50

1999

R42763.-R42766.

R42767.

1977

R05576.-R05578.

--

--

2001

 R54450.–R54453.

  --

Related Variables: In addition to the information collected on the respondent, most surveys have also collected age data on household members. See the "Household Composition" section of this guide for more information.

Survey Instruments: The respondent’s age and date of birth were derived from the 1966 Household Screener.  The respondent’s age or date of birth was subsequently collected in the “Household Roster” section of the questionnaire.  If the respondent’s age or birth date is asked in a particular survey year, an open coded answer box for the respondent will be found in the “Household Roster.”

User Notes: Users are encouraged to carefully examine all age and birth date variables when performing any age-related analysis. Birth data collected at the time of screening may have been provided by a family member, giving rise to possible inconsistencies when comparing a respondent's reported age with age calculated from date of birth. In cases where age was unknown, interviewers were directed to obtain a "best estimate" of a respondent's "exact age" at the time of screening and to make corrections later if possible. Finally, a respondent may be inconsistent in reporting her age during different interviews.

There are varying numbers of out-of-scope cases in the Young Women cohort for two reasons:  (1) the birth date variables in a handful of cases are inconsistent with the stated age of the respondent and (2) some borderline cases that may actually be in scope for the calendar year of the survey are not necessarily in scope at the time the interview took place.  CHRR has investigated causes of birth date inconsistencies and has discovered that they arise from birth data originally provided by the Census Bureau.  Unfortunately, these data are generally not recoverable because many of the affected respondents have since attrited.  An additional difficulty is that the date of birth for some cases is not reported.  Data are not available for two individuals who were reported deceased between 1968 and 1969.

It may be to the user’s advantage to calculate his or her own variable for age based on the reported date of birth.  When birth date variables are either unavailable or out of scope, the user may wish to investigate other age-related variables, such as schooling information, in order to establish age.

In select survey years, an ‘Age at Interview’ variable was created even for those not interviewed in that particular year.  Age distributions in the codebook are reported for noninterviewed as well as interviewed respondents; interested users may calculate a more accurate age distribution by deleting respondents who were not interviewed in a given year.  Table 4.1.2 presents age distributions for interviewed respondents by survey year.

Table 4.1.2 Ages of Interviewed Respondents by Survey Year: 1968-2001

 

Survey Year

Age1

68

69

70

71

72

73

75

77

78

80

82

83

85

87

88

91

93

95

97

99

01

14

130

--

--

--

--

--

--

--

--

--

--

--

--

--

--

--

--

--

--

--

--

15

538

126

--

--

--

--

--

--

--

--

--

--

--

--

--

--

--

--

--

--

--

16

575

525

128

--

--

--

--

--

--

--

--

--

--

--

--

--

--

--

--

--

--

17

524

554

518

125

--

--

--

--

--

--

--

--

--

--

--

--

--

--

--

--

--

18

529

505

540

506

123

--

--

--

--

--

--

--

--

--

--

--

--

--

--

--

--

19

528

510

481

539

496

115

--

--

--

--

--

--

--

--

--

--

--

--

--

--

--

20

499

504

482

466

529

479

--

--

--

--

--

--

--

--

--

--

--

--

--

--

--

21

482

479

488

481

469

498

114

--

--

--

--

--

--

--

--

--

--

--

--

--

--

22

386

459

463

489

469

439

462

--

--

--

--

--

--

--

--

--

--

--

--

--

--

23

398

362

441

453

475

453

480

110

--

--

--

--

--

--

--

--

--

--

--

--

--

24

356

373

347

440

444

455

429

448

103

--

--

--

--

--

--

--

--

--

--

--

--

25

186

338

368

339

427

423

438

465

417

--

--

--

--

--

--

--

--

--

--

--

--

26

5

175

327

364

335

412

427

416

448

102

--

--

--

--

--

--

--

--

--

--

--

27

--

5

169

328

360

321

405

423

396

415

--

--

--

--

--

--

--

--

--

--

--

28

--

--

4

172

324

350

399

420

399

431

101

--

--

--

--

--

--

--

--

--

--

29

--

--

--

4

164

312

304

381

398

387

407

98

--

--

--

--

--

--

--

--

--

30

--

--

--

--

3

159

329

383

362

388

423

399

--

--

--

--

--

--

--

--

--

31

--

--

--

--

--

3

299

290

369

383

367

411

104

--

--

--

--

--

--

--

--

32

--

--

--

--

--

--

151

324

274

346

364

353

405

--

--

--

--

--

--

--

--

33

--

--

--

--

--

--

4

294

309

363

364

341

427

107

--

--

--

--

--

--

--

34

--

--

--

--

--

--

--

147

278

265

331

362

365

400

98

--

--

--

--

--

--

35

--

--

--

--

--

--

--

4

142

302

349

322

368

417

394

--

--

--

--

--

--

36

--

--

--

--

--

--

--

--

4

270

254

344

370

354

399

--

--

--

--

--

--

37

--

--

--

--

--

--

--

--

--

142

290

247

356

354

355

95

--

--

--

--

--

38

--

--

--

--

--

--

--

--

--

4

258

283

360

364

342

386

--

--

--

--

--

39

--

--

--

--

--

--

--

--

--

--

135

246

271

357

345

387

84

--

--

--

--

40

--

--

--

--

--

--

--

--

--

--

4

134

294

352

334

341

369

--

--

--

--

41

--

--

--

--

--

--

--

--

--

--

--

4

265

252

337

335

368

77

--

--

--

42

--

--

--

--

--

--

--

--

--

--

--

--

130

289

239

340

318

348

--

--

--

43

--

--

--

--

--

--

--

--

--

--

--

--

--

260

286

321

318

351

76

--

--

44

--

--

--

--

--

--

--

--

--

--

--

--

--

127

253

327

311

304

358

--

--

45

--

--

--

--

--

--

--

--

--

--

--

--

--

3

121

238

300

300

350

77

--

46

--

--

--

--

--

--

--

--

--

--

--

--

--

--

3

266

297

287

310

335

--

47

--

--

--

--

--

--

--

--

--

--

--

--

--

--

--

239

218

276

300

331

71

48

--

--

--

--

--

--

--

--

--

--

--

--

--

--

--

120

255

288

294

288

322

49

--

--

--

--

--

--

--

--

--

--

--

--

--

--

--

3

227

209

294

274

332

50

--

--

--

--

--

--

--

--

--

--

--

--

--

--

--

--

117

243

279

285

287

51

--

--

--

--

--

--

--

--

--

--

--

--

--

--

--

--

3

220

213

271

279

52

--

--

--

--

--

--

--

--

--

--

--

--

--

--

--

--

--

110

238

273

282

53

--

--

--

--

--

--

--

--

--

--

--

--

--

--

--

--

--

3

219

205

253

54

--

--

--

--

--

--

--

--

--

--

--

--

--

--

--

--

--

--

113

231

256

55

--

--

--

--

--

--

--

--

--

--

--

--

--

--

--

--

--

--

3

214

197

56

--

--

--

--

--

--

--

--

--

--

--

--

--

--

--

--

--

--

--

110

212

57

--

--

--

--

--

--

--

--

--

--

--

--

--

--

--

--

--

--

--

3

203
58 -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 106
59 -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 3

Total Int'd

5159

4930

4766

4714

4625

4424

4243

4108

3902

3650

3650

3547

3720

3639

3508

3400

3187

3019

3049

2900

2806

Not Int'd

--

229

393

445

534

735

916

1051

1257

1358

1509

1612

1439

1520

1651

1759

1972

2140

2110

2259

2353

Birth Year n/a

23

15

10

8

7

5

2

3

3

3

3

3

2

3

2

2

2

3

2

3

3
1 Age of respondent is calculated as of June 30 of the interview year using the 1968 date of birth variables (R00420.10, R00420.11, and R00420.12).

 


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