Chapter 2 part 2

Before each survey period begins, the Census Bureau generates lists of respondents to be interviewed and distributes them to 12 regional offices. Current addresses and contact information are generated from data collected during the last interview and through a postal check conducted by Census, and cases are assigned to interviewers who live in the same geographic area as the respondent. Interviewers then receive copies of the questionnaire (or a laptop computer for CAPI/CATI interviews), respondents' Household Record Cards, and flashcard and information booklets.

In each survey round, interviewers are responsible for contacting each respondent in their caseload and for using additional local level resources to locate those respondents who have moved since the last interview. Respondents who have moved outside the geographic district of the original interviewer are assigned to another unless there are no personnel nearby. In the latter event, an effort is made to interview the respondent by telephone.

Each respondent to be interviewed is sent various materials designed to encourage continued participation. Advance letters thanking respondents for taking part in the interviews and informing them of the coming survey are mailed prior to each interview period. Fact sheets highlighting recent research findings from each cohort's survey data are also provided. Respondents who initially refuse to participate in a survey are sent letters and some additional materials by the regional offices designed to encourage their continued participation and are once again contacted by local level interviewers to secure the interview.

While the type of survey, personal or telephone, determines the chief mode of contact, an alternate contact method is used for certain respondents. During a personal survey, for example, those respondents who live long distances from the Census interviewer's base of operation or those for whom the Census supervisor has decided that another contact method is warranted are contacted by telephone. Although survey instruments are written in English only, multilingual interpreters are made available by the regional offices to interviewers who need them.

In 1995, respondents in the two women's cohorts were interviewed during the same time period; a single computer-assisted personal interview replaced the paper-and-pencil interview (PAPI) instruments used during the previous interviews. While data were collected simultaneously for the two cohorts, they were released separately by cohort. This computer-assisted interview has continued on a biennial basis.

The average length of an interview varies depending on the type conducted, with personal PAPI interviews lasting 50-60 minutes, CAPI interviews lasting about 70 minutes, and CATI interviews averaging 20-25 minutes. No stipends have been paid to Original Cohort respondents for their participation.

2.6 Eligible Sample & Reasons for Noninterview

In general, respondents selected for interviewing each year are those who participated in the initial survey and who are alive, residing within the United States at the interview date, and noninstitutionalized. (If a respondent had joined the Armed Forces, she would also have been excluded from interview during her enlistment, but no Mature Women respondents were members of the military during the survey period.) However, the criteria used to select the eligible sample--respondents whom the Census Bureau attempts to interview in a given round--have varied somewhat over the years.

Beginning in 1968, any respondent who had refused to be interviewed during a previous round was dropped from the eligible sample. Beginning in 1971, respondents were also dropped from the eligible sample if they had not been interviewed in two consecutive surveys for reasons other than death or refusal (for example, respondents who could not be located or contacted during the field period--those with 'Reason for Noninterview' codes of 1, 2, 3, 4, 5, 6, 8, or 11). In 1982, Census ceased dropping individuals for these two reasons but did not attempt to reinterview those already dropped. For example, a respondent who missed the 1979 and 1981 interviews, or any two consecutive interviews prior to that year, for a reason other than death or refusal would not be eligible to participate in 1982 or any subsequent year. Similarly, a respondent who refused to participate in 1981 or any earlier survey would not be eligible in 1982 or any later survey. However, respondents who refused to participate or missed their second consecutive interview in 1982 are retained in the sample and are eligible for all subsequent interviews, unless they have died or been institutionalized. The User Notes after Table 2.6.2 describe how dropped respondents can be identified.

Table 2.6.1 below depicts reasons for exclusion from the eligible sample and the years each applied; Tables 2.6.3 and 2.6.4 later in this section present reasons for noninterview across survey years.

Each survey year, CHRR creates a cumulative 'Reason for Noninterview' variable for the full sample of respondents. Variable reference numbers for this series from 1968 to 2001 are: R00856., R00884., R01338., R02053., R02883., R03084., R03295., R04555., R04912., R05284., R06664.10, R07215.10, R07833.10, R08878.10, R10093.10, R16012., R34981., R42670., and R63203. This created variable is a combination of (1) the noninterview reasons provided by Census for the subset of respondents designated as eligible for interview in that survey year and (2) the reason for noninterview assigned during a previous survey to out-of-scope respondents. For several surveys, CHRR released an additional variable reflecting the reasons for noninterview for only those respondents with whom interviews were attempted that year. This type of variable is available in 1974 (R07755.) and in 1992 (e.g., R10093.). The number of respondents that Census designates as eligible for interviewing fluctuates by survey year.

Instructions to interviewers on how to code a respondent's reason for noninterview appear within the Interviewer's Reference Manuals (or Field Representative's Manuals). The set of noninterview coding categories present during the initial survey years has been supplemented over the years with additional reasons for noninterview, and the meanings of existing categories have been refined. Table 2.6.2 presents the raw coding categories present on the public data files and specifies the survey years during which each category was utilized.

Table 2.6.2 Conceptual & Raw Coding Categories for the Reason for Noninterview Variables

Conceptual Category	Raw Coding Category¹	Code & Survey Years
CAN'T LOCATE	Unable to locate [contact] R - reason not specified	[1]	All (1967-present)
CAN'T LOCATE	[Unable to locate R] - mover - no good address	[4]	All
INTERVIEW IMPOSSIBLE	[Unable to locate R] - mover - good address given but interview impossible to obtain (e.g., "moved to Germany" or "lives too far from PSU - distance too great")²	[2]	All
	[Unable to locate R] - mover - good address given but unable to obtain interview after repeated attempts, etc.	[3]	All
	[Unable to locate R] - nonmover - unable to obtain interview after repeated attempts, etc.	[5]	All
	Temporarily absent	[6]	All
	Other	[11]	All
REFUSAL	Refusal	[9]	All
REFUSAL	Congressional refusal³	[14]	1984-present
OUT OF SCOPE	In Armed Forces	[7]	All
	Institutionalized	[8]	All
	Moved outside U.S. (other than Armed Forces)	[13]	1979-present
DECEASED	Deceased	[10]	All
DROPPED	Non-interview for two years, R dropped from sample	[12]	1971-present

¹ Specific instructions to Census interviewers on use of these coding categories can be found in the cohort-specific Interviewer's Reference Manuals.
² Beginning in the 1979 survey year, the separate "moved outside the U.S." coding category was added as a reason for noninterview and the "unable to locate" coding category no longer included those respondents who had moved outside the United States.
³ Congressional refusal refers to a congressional representative requesting a respondent not be contacted again for an NLS survey after a respondent has completed one or more survey rounds.

The reason for noninterview coding categories depicted in Tables 2.6.3 and 2.6.4 below were constructed from the raw coding categories as shown in Table 2.6.2. For example, the conceptual category "can't locate" is the sum of codes "1" and "4." Tables 2.6.3 and 2.6.4 depict the number of respondents not interviewed by survey year, reason, and race.

			Reason for Noninterview
Survey Year	Total Interviewed	Total Not Interviewed	Can't Locate	Interview Impossible	Refusal	Out of Scope¹	Deceased	Dropped²
1968	4910	173	49	25	76	1	22	--
1969	4712	371	50	69	210	7	35	--
1971	4575	508	56	65	292	6	60	29
1972	4471	612	39	49	389	2	72	61
1974	4322	761	41	31	479	5	101	104
1976	4172	911	34	40	580	7	131	119
1977	3964	1119	22	49	761	6	140	141
1979	3812	1271	21	27	867	11	176	169
1981	3677	1406	18	17	963	9	216	183
1982	3542	1541	15	26	1061	8	238	193
1984	3422	1661	31	25	1113	13	285	194
1986	3335	1748	38	35	1130	10	341	194
1987	3241	1842	30	45	1195	14	364	194
1989	3094	1989	29	49	1265	21	431	194
1992	2953	2130	62	18	1286	24	546	194
1995	2711	2372	69	91	1321	33	664	194
1997	2608	2475	96	49	1293	38	805	194
1999	2467	2616	81	68	1311	48	914	194
2001	2318	2765	64	86	1285	57	1079	194

Note: This table is based on R00856., R00884., R01338., R02053., R02883., R03084., R03295., R04555., R04912., R05284., R06664.10, R07215.10, R07833.10, R08878.10, R10093.10, R16012., R34981., R42670., and R63203.
¹ Beginning with the 1979 survey, "moved outside the U.S." became a separate out-of-scope coding category. Respondents who could not be interviewed during the 1968-77 surveys because their residence--either within or outside of the U.S.--was too far away were coded within the "interview impossible" category. Out-of-scope counts for pre-1979 survey years thus may be understated.
² Respondents who had been noninterviews for two consecutive survey years due to reasons other than refusal or death were eliminated from the eligible sample beginning with the 1971 interview. After the 1982 interview, no additional respondents were dropped based on this rule.

Survey Year	Total Interviewed		Total Not Interviewed		Reason for Noninterview
Survey Year	Total Interviewed		Total Not Interviewed		Can't Locate		Interview Impossible		Refusal		Out of Scope¹		Deceased		Dropped²
	Non-black	Black	Non-black	Black	Non-black	Black	Non-black	Black	Non-black	Black	Non-black	Black	Non-black	Black	Non-black	Black
1968	3576	1334	117	56	26	23	16	9	60	16	1	0	14	8	--	--
1969	3418	1294	275	96	31	19	48	21	171	39	3	4	22	13	--	--
1971	3330	1245	363	145	29	27	52	13	228	64	1	5	33	27	20	9
1972	3264	1207	429	183	20	19	36	13	298	91	0	2	36	36	39	22
1974	3157	1165	536	225	19	22	24	7	369	110	3	2	55	46	66	38
1976	3049	1123	644	267	18	16	30	10	443	137	3	4	74	57	76	43
1977	2892	1072	801	318	12	10	36	13	583	178	3	3	79	61	88	53
1979	2781	1031	912	359	13	8	14	13	663	204	10	1	103	73	109	60
1981	2685	992	1008	398	9	9	13	4	738	225	6	3	126	90	116	67
1982	2583	959	1110	431	11	4	16	10	816	245	5	3	139	99	123	70
1984	2510	912	1183	478	16	15	16	9	855	258	11	2	161	124	124	70
1986	2453	882	1240	508	19	19	22	13	872	258	7	3	196	145	124	70
1987	2383	858	1310	532	18	12	34	11	915	280	10	4	209	155	124	70
1989	2277	817	1416	573	15	14	29	20	977	288	13	8	258	173	124	70
1992	2170	783	1523	607	38	24	13	5	1008	278	15	9	325	221	124	70
1995	2012	699	1681	691	36	33	65	26	1043	278	15	18	398	266	124	70
1997	1939	669	1754	721	67	29	35	14	1026	267	22	16	480	325	124	70
1999	1848	619	1845	771	53	28	56	12	1029	282	30	18	553	361	124	70
2001	1749	569	1944	821	43	21	67	19	1015	270	35	22	660	419	124	70

Note: This table is based on R00023. (race), R00856., R00884., R01338., R02053., R02883., R03084., R03295., R04555., R04912., R05284., R06664.10, R07215.10, R07833.10, R08878.10, R10093.10, R16012., R34981., R42670., and R63203.
¹ Beginning with the 1979 survey, "moved outside the U.S." became a separate out-of-scope coding category. Respondents who could not be interviewed during the 1968-77 surveys because their residence--either within or outside of the U.S.--was too far away were coded within the "interview impossible" category. Out-of-scope counts for pre-1979 survey years thus may be understated.
² Respondents who had been noninterviews for two consecutive survey years due to reasons other than refusal or death were eliminated from the eligible sample beginning with the 1971 interview. After the 1982 interview, no additional respondents were dropped based on this rule.

2.5 Interview Methods

2.6 Eligible Sample & Reasons for Noninterview