# Presentation: 230504

## NCHS Research Data Center

**Wilbur C. Hadden**

## What is the Research Data Center?

- A NCHS data access program
- An office, with staff, within NCHS
- A physical space, with security
- A research facility, with computers

## Access to NCHS Data

- Public use data files
- Restricted access
- Tabulations
- Reports, publications, web-site
- Journal articles

## Authority for Confidentiality

- Public Health Service Act, section 308(d)
- Informed consent of survey participants and data providers

## Identified Data

- Data records are identified by unique data elements
- Name
- Social Security Number
- Hospital ID number

## Identifiable Data

- Data are made identifiable with data elements that can be related to unique identifiers
- Address
- Size – e.g. number of beds, height
- Specialization – e.g. having a level 1 shock trauma center, or being a farm owner/manager

## Statistical Disclosure

- When information on data providers can be inferred from published data

## Data Accessible in RDC

- Data that are potentially identifiable
- Physician age and sex in NAMCS
- Data linked to geographic identifiers
- State, county, Census tract
- Data linked to provider characteristics
- Hospital size

## RDC Data Access Methods

- On-site access
- Remote access
- RDC staff assistance / collaboration

## Data Preparation

- Users cannot take data into RDC
- RDC staff prepare data files for users
- Users can provide data to RDC staff
- NCHS policy is ***not*** to release user data to others
- RDC staff will link user data to NCHS data

## Slide 11

## On-Site Access

- Controlled access facility
- Isolated computer network
- No e-mail
- No internet
- No mountable media on computers
- Users cannot take materials into computer room
- No more than 3 users per project

## Slide 13

## Output Disclosure Review

- Only printer is located behind locked door
- RDC staff person retrieves output
- Disclosure review performed before output given to users

## Remote Access

- Send SAS programs to RDC by e-mail
- SAS program scanned – a few SAS commands and not allowed
- Program executed
- Automated disclosure review of program output
- Output returned by e-mail

## Software in RDC

- SAS (only language available on ANDRE)
- SUDAAN
- Fortran
- HLM
- Stata
- Limdep
- text editors/viewers

## To Gain Access to NCHS RDC

- Visit the RDC (optional, but suggested)
- Discuss proposal with RDC staff
- Submit research proposal
- Discuss proposal with RDC staff and revise
- Pass NCHS review of proposal
- Sign “Research Affidavit of  Confidentiality”

## Proposal Contents

- Identification of researcher(s)
- Source of funding
- Description of proposed research
- Detailed specification of data sought
- Detailed specification of any user supplied data
- Software requirements

## Proposal Evaluation Criteria

- Risk of disclosure of confidential data
- Scientific merit and technical feasibility
- Availability of resources in RDC
- Consistency with NCHS mission

## Cost per Project

| File construction and setup | $500 per day |
| --- | --- |
| On-site | $1000 per week |
| Remote Access |  |
|   NSFG-CDF | $500 per year |
|   NHIS-polio | $500 per year |
|   Files < 130k records | $500 per month |
|   Files > 130k records | $1000 per month |

## Number of RDC Clients

|  | 2000 | 2001 | 2002* |
| --- | --- | --- | --- |
| Remote Access | 7 | 3 | 3 |
| On Site | 4 | 10 | 11 |
| Staff Programming | 1 | 1 | 5 |

- *January to July 2002

## Jobs Processed at RDC

|  | 2000 | 2001 | 2002* |
| --- | --- | --- | --- |
| Remote Access | 888 | 441 | 456 |
| On Site | 570 | 1006 | 1645 |
| Staff Programming | 81 | 212 | 760 |

- *January to July 2002

## Projects by Data System

|  | 2000 | 2001 | 2002* |
| --- | --- | --- | --- |
| NHIS | 6 | 7  | 8 |
| NSFG | 3 | 7 | 8 |
| NHANES | 1 | 2 | 1 |
| NAMCS | 1 | 1 | 4 |
| Other | -- | 2 | 5 |
| *January to July 2002 |  |  |  |

## http://www.cdc.gov/nchs/r&d/rdc.htm