0235-niosh-08-SSB

Supporting Statement

CHILDHOOD INJURY AND

ADULT OCCUPATIONAL INJURY SURVEYS

OMB No. 0535-0235

B. COLLECTION OF INFORMATION EMPLOYING STATISTICAL METHODS:

1. Describe (including a numerical estimate) the potential respondent universe and any sampling or other respondent selection method to be used. Data on the number of entities (e.g., establishments, State and local government units, households, or persons) in the universe covered by the collection and in the corresponding sample are to be provided in tabular form for the universe as a whole and for each of the strata in the proposed sample. Indicate expected response rates for the collection as a whole. If the collection has been conducted previously, include the actual response rate achieved during the last collection.

Sampling units for this data collection will be drawn from the NASS list sampling frame of about 2 million farm and ranch operations. Samples will be drawn after data collected during the 2007 Census of Agriculture is captured to the NASS list frame, in order to maximize the accuracy of the list. For the childhood farm injury survey, 50,000 sample units will be selected nationwide by simple random sampling, with the samples divided equally among the four Bureau of the Census major region classifications: Northeast, Mid-west, South, and West. The adult occupational farm injury survey will use a sub-sample of 25,000 farms from the 50,000 selected for the childhood injury survey, with the same regional stratification. NASS will be utilizing one questionnaire for both surveys. The childhood farm injury questions will be asked of the entire 50,000 selected operations. The adult occupational farm injury questions will only be asked of the 25,000 sub-sampled operations. Data for both surveys will be collected by telephone at the same time.

The adjusted response rate is expected to be approximately 80 percent for these surveys. Following the previous submission of this OMB docket, NIOSH received a request from OMB, asking for two additional methods of calculating the response rate. In the following table we have included the Crude Response Rate, the OMB Response Rate and the Adjusted Response Rate.

Year	Completes (C)	Out of business (OB)	Contact Refusal (CR)	Not Contacted (NC)	Total (T)	Crude Response1	OMB Response2	Adjusted Response3
2001 4	23,196	3,974	9,254	12,846	49,270	55.1%	53.4%	74.6%
2002	26,424	4,320	8,600	10,656	50,000	61.5%	59.8%	78.1%
2004 Race 5	18,663	1,385	4,484	6,780	31,312	64.0%	63.4%	81.7%
2004 Hispanic 5	12,084	795	3,514	4,770	21,163	60.9%	60.2%	78.6%
2005	29,564	3,229	8,092	9,115	50,000	65.6%	64.4%	80.2%
2006	27,277	2,853	8,462	9,659	48,251	62.4%	61.3%	78.1%
1. Crude Response = (C + OB)/T
2. OMB Response = C/(T- OB -(NC x OB/(C + OB)))
3. Adjusted Response = (C + OB)/(T - NC)
4. 2001 survey covered racial minority and Hispanic farm operations only. Survey response numbers were combined.
5. 2004 survey covered racial minority and Hispanic farm operations only. Survey response numbers were reported separately by race and ethnicity.

2. Describe the procedures for the collection of information.

Respondents will be sent an advance letter and brochure (attachment G) explaining the purpose of the survey and information on the type of data being collected. The actual questionnaire is not mailed out to the respondents prior to the data collection phase, only the publicity materials. Telephone interviewing will begin on March 1, 2009; the data collection instrument is in attachment H. If the respondent is not available at the first contact attempt, additional telephone calls will be made at various times, during the day and evening hours, and on different days of the week for the two month data collection period. Each respondent will be attempted at least 10 times during the data collection period in an attempt to increase our response rates. The subject will be asked if she/he is willing to participate. If the respondent indicates that the time is not convenient a call back time will be arranged. As the interview begins, the subject will be reminded that, although complete cooperation is important to the success of the project, she/he may refuse to answer any specific questions and may terminate her/his participation at any time.

3. Describe methods to maximize response rates and to deal with issues of non-response. The accuracy and reliability of information collected must be shown to be adequate for intended uses. For collections based on sampling a special justification must be provided for any collection that will not yield "reliable" data that can be generalized to the universe studied.

To improve response and increase the number of contacts, 6 State telephone calling centers will be utilized compared to 5 for the previous study. These NASS Data Collection Centers (DCC) have been optimized to collect data in the most efficient manner possible. Special training will be provided to the statisticians in the six DCC’s for this survey. They will in turn, provide survey specific training to all of the NASDA enumerators that will be conducting this survey by telephone. The enumerators will be able to ask questions in a consistent and professional manner, as well as answer any questions that respondents may have about the survey and why this data is important to them.

Pre-survey letters and brochures (attachment G) are mailed to each potential respondent informing them of the purpose of the survey and highlighting results from the previous study. Calling centers have implemented special caller-identification information so that contacts can distinguish NASS calls from other, unknown, telephone solicitors. Hopefully, this will reduce the incidences where individuals will not answer the telephone because they cannot identify the caller. Also, in preparation for the 2007 Census of Agriculture, NASS has performed extensive list improvement efforts (including a special focus on identifying minority owned farms),which should improve the quality of the sample and reduce non-response due to disconnected telephones, incorrect telephone numbers, or name and address errors.

The possibility of non-response bias will exist because of telephone non-response. Budget constraints will not allow for field interview follow-up of these non-respondents. Therefore, adjustments for coverage and non-response will be made by calibrating the weights of the responding records of the survey to adjust to the characteristics of the 2007 Census of Agriculture by age, gender, and geographic area.

With the anticipated response rate, the resulting summary data will provide reliable and useable estimates of childhood agricultural injuries and adult occupational farm injuries. Information on children injured on farms while visiting a farm should be sufficient to estimate the frequency of such injuries but may be limited in providing estimates related to the circumstances of these injuries, especially at the regional level.

4. Describe any tests of procedures or methods to be undertaken.

The procedures and methods used for this survey are similar to other probability surveys conducted by NASS. The data collection instrument will be pretested to improve the data quality by reducing non-sampling error.

5. Provide the name and telephone number of individuals consulted on statistical aspects of the design and the name of the agency unit, contractor(s), grantee(s), or other person(s) who will actually collect and/or analyze the information for the agency.

NASS and NIOSH will work collaboratively on survey design and data collection. Statisticians in each of the 45 NASS field offices will review the State level

samples and designate a project contact for the State. NASS will collect the data utilizing its network of DCC’s and NASDA enumerators located in 6 states, with good geographic dispersion. NIOSH will be responsible for analysis and dissemination of the data. NASS Survey Administration Branch and Survey Sampling Branch will provide consultation on matters concerning quality control, sampling estimates, and sampling errors.