The Industry and Occupation (I&O) data items are one of the least well understood in the patient record and the least frequently reported to the California Cancer Registry (CCR). Consider this fact: looking at the 25 most frequent I&O entries in the database, over 330,000, or almost a third, are entered as "not recorded" or almost a third, are entered as "not recorded" or "retired."

It is acknowledged that much of the problem with the I&O data items results from the failure of admitting clerks and physicians to record the patient's longest held Occupation and the Industry associated with the Occupation. The main purpose of this article is to provide some simple definitions and guidelines that registrars can keep in mind to make the most out of I&O data, despite the lack of information in the medical record. Before these definitions and guidelines are covered, the status of the coding effort will be discussed along with the significance of the data for cancer research.

I&O CODING STATUS

I joined the CCR in March, 1995 as a full-time I&O Coder, and learned the 1990 U.S. Census I&O Coding system in a one week coding class with instructors from NCHS (National Center for Health Statistics) and NIOSH (National Institute of Occupational Safety and Heal

Because the position had been vacant since 1991, there existed a backlog of almost 400,000 uncoded I&O text fields. Fortunately, Region 9's (Los Angeles County's) I&O Coder has been on the job for a number of years, otherwise the backlog would have been much worse! Several other regions had I&O Coders, but they stopped coding in 1991 due to budget constraints.

The design of the coding software by our Data Processing Department has greatly reduced the backlog. In the first step, the 3,350 most frequent I&O text fields in the database were assigned 1990 U.S. Census I&O Codes. These fields were then compared to those in the backlog, and the 200,000 records that matched were assigned an I&O Code by the software. This process took a month to complete. Coding these same fields one at a time would have taken at least two years.

An additional 50,000 I&O fields have been coded since the initial 200,000, leaving approximately 140,000 in the backlog. Software developed by NIOSH, which should be available this summer, will cut that number down even further. It is programmed with all of the coding rules and automatically assigns 1990 I&O Codes.

To date, 900,000 I&O data items have been processed. Most of them were coded with the 1980 version of the U.S. Census Codes. A mostly automated procedure will convert these to 1990 codes.

RESEARCH USING I&O DATA ITEMS

The purpose of assigning a code to the I&O data items is that as many as 21,000 Industry Titles are then organized into 236 U.S. Census categories and up to 30,000 Occupation Titles are reduced to 501 categories. This provides a basis for research into the occurrence of cancer within different Industry and Occupation categories. The three digit code that corresponds to each category makes it possible for scientists to tabulate the data for statistical studies.

Eva Glazer, Ph.D., M.D., one of the scientists who will be studying these data, elaborates on the significance of I&O data and her research plans. "Epidemiologists estimate that approximately four percent of cancers may be associated with occupational and industrial exposures," she said. "For California this works out to almost 5,000 cases a year, some of which may show up well after retirement age.

"Many carcinogens were first identified through studies of workers in particular industries and occupations. Monitoring cancer incidence by occupation and industry is still an important tool for primary and secondary cancer prevention; its usefulness will increase as the number of cases for which we have data on the longest-held occupation and industry increases.

"Our first step will be to calculate the proportional incidence of specific cancers in particular industries and occupations, such as agriculture, forestry, electronics, etc. At the time of the next census, when the Bureau of the Census publishes the numbers of persons working in various industries and occupations in California, we hope to combine our industry and occupation data with census data to estimate standardized incidence ratios of specific cancers for major industries and occupations."

I&O DEFINITIONS

Of the two data items, the Industry field is the most often left blank. This may be in part because the U.S. Census' definition of Industry is different from our everyday understanding of the word. To the U.S. Census, Industry is defined as, "the employer's kind of business." This means that any organization that hires employees is considered to be an Industry. For example, video stores, hospitals, churches, schools, and the Post Office are all Industries. On the other hand, broad categories of businesses that are commonly referred to as Industries do not fit the U.S. Census definition. "The Oil Industry," is really many Industries including oil extraction, oil refining, oil products manufacturing, wholesalers of oil products, and gas stations, among others.

For the purpose of coding, it is important to know the Industry because the code assigned to the Occupation often depends on the Industry code. For example, teachers who work at preschools and kindergartens, grade schools, high schools, and colleges are all assigned different Occupation codes.

Fortunately, the U.S. Census definition of Occupation, "the employee's kind of work," is the same as the common definition. Veterinarian, lawyer, noodle maker, secretary, frog farmer, and priest are all examples of Occupations. A person's Occupation is the answer to the question, "What do you do for a living?"

I&O DATA ITEM REQUIREMENTS

Volume One, Section III.2.13, defines the I&O data items in the following way:

Industry: the kind of industry associated with the longest-held occupation at the time of diagnosis Occupation: the patient's longest-held occupation at the time of diagnosis

If several Industries or Occupations are listed, please enter all of the titles and separate them by commas or slashes. Be sure to include an "*" to indicate when it is not certain that the Occupation or Occupations listed are the longest held.

"Retired," or "unemployed," are not adequate entries by these definitions. Usually, it is the admitting clerk who records this type of entry on the face sheet. However, additional information in the medical record may be overlooked. In 1991, Dawn Leytem, Quality Control Specialist, and Kathleen Thrasher, Statistician, of the CCR performed an I&O reabstracting audit and found an 18% discrepancy rate between what was in the database and what was found in the medical record for the I&O data items. As a result of this audit, Volume One was updated to include several hints designed to help the abstracter find I&O data items in the medical record. Suggestions included reviewing physical exams and previous admissions for the I&O data.

SUGGESTIONS FOR IMPROVING THE I&O DATA ITEMS

Here are nine simple suggestions to improve the quality of I&O data items.

1. Do not leave fields blank If there are no I&O data, enter NR for "Not Recorded." When "Retired," is the only I&O information available, it may be entered instead of "NR."

2. Do not enter extraneous information Text such as, "retired since 1984," or "NOS," does not add anything that would help assign a code. In addition, automatic coding software will have trouble interpreting this extra information.

3. Avoid the use of abbreviations except for NR Avoid abbreviations when possible, except for well known ones like CPA, LVN, RN, etc. Abbreviations can confuse both human and software coders.

4. Do not use "RETIRED" to describe an Occupation "Retired," does not add any information that can be used to assign a code. If there is any occupation information, omit "Retired." For example, use "Fireman," instead of, "Retired Fireman."

5. Put the industry and occupation fields in the appropriate place Several thousand I&O data items in the database are entered in the wrong text field.

6. Avoid the use of company names unless the Industry is not described Although a description of the Industry is preferred, if a company name is the only Industry information available, please enter it. It would also be helpful to know the city where the company is located.

7. Try to use terms that describe the Occupation, i.e., "Electrical Engineer" rather than "Engineer" See the tables accompanying this article for some examples of inadequate vs. adequate Industry and Occupation titles.

8. Use "Own Home" for Industry and "Homemaker as Occupation for Housewives/Househusbands Please make it clear whether the person is taking care of their own home and family or working outside of the home as a housekeeper.

9. For military personnel, include the branch of service in the Industry field and the person's rank in the Occupation field.
If a patient has a specific Occupation in the military (i.e., pilot, surgeon, cook), please enter this information in addition to their rank.

RECOMMENDED REFERENCE

Ideally, every registrar will refer to a copy of the NCHS publication, "Guidelines for Reporting Occupation and Industry on Death Certificates," when entering I&O data items. The NCHS requires the same Industry and Occupation information on death certificates as the CCR does on the medical record. This booklet is a valuable resource because it contains an extensive list of adequate vs. inadequate Industry and Occupation titles.

Copies of "Guidelines..." have been ordered from the NCHS and will be distributed to the regional registries in the near future

ASSISTANCE AND TRAINING

I appreciate the extra effort it will take to maximize the quality of the I&O data. If I can be of any assistance, please contact me at (916) 322-1301 or through email at curr108w@wonder.em.cdc.gov. Also, I am available to give an hour-long seminar to groups of registrars or admitting clerks on the topics covered in this article.

Adequate vs. Inadequate Industry Titles

INADEQUATE	ADEQUATE
Bakery	Bakery plant, Wholesale bakery, Retail bakery
Dairy	Dairy farm, Wholesale dairy products, Dairy products manufacturing, Retail dairy
Factory	Steel rolling mill, Aircraft factory, Automobile plant
Farm	Cattle ranch, Crop farm, Chicken ranch, Cattle and wheat farm, Fish farm
Freight company	Motor freight (trucking company), Air freight, Railroad freight, Water transportation
Mine	Coal mine, Bauxite mine, Sand and gravel pit, Iron mine
School	Preschool, Kindergarten, Elementary School, High School, Adult School, College
Title Company	Title abstract company, Title and trust company, Title guaranty company, Title insurance company
Utility Company	Electric utility company, Gas utility company, Electric and gas utility company, Water utility company

Table 1. Adequate vs. Inadequate Industry Titles. Examples of adequate and inadequate Industry titles are presented. They are adopted from the NCHS "Guidelines" booklet and the "Alphabetical Index of Industries and Occupations," of the U.S. Census.

Adequate vs. Inadequate Occupation Titles

INADEQUATE	ADEQUATE
Analyst	Food analyst, Budget analyst, Computer systems analyst, Procedures analyst
Clerk	Accounting clerk, Stock clerk, Shipping clerk, Sales clerk
Consultant	Financial consultant, Legal consultant, Marketing consultant, Tax consultant
Counselor	Educational counselor, Personnel counselor, Rehabilitation counselor, Family and marriage counselor
Engineer	Civil Engineer, Locomotive engineer, Aerospace engineer, Operating engineer
Manager	Kitchen manager, Office manager, Personnel manager, Public relations manager, Warehouse manager
Mechanic/Repairer	Automobile mechanic, Airplane engine mechanic, Copy machine repairer, Elevator mechanic
Supervisor/Foreperson	Ranch foreperson, Carpenter foreperson, Recreation supervisor, Service supervisor

Table 2. Adequate vs. Inadequate Occupation Titles. Examples of adequate and inadequate Occupation titles are presented. They are adopted from the NCHS "Guidelines" booklet and the "Alphabetical Index of Industries and Occupations," of the U.S. Census.