BOSTON — Delaware ranked first and Louisiana last in a University of Massachusetts study that tried to measure where workers are treated best, based on factors including job opportunities, job quality and workplace fairness.

Rounding out the top five best states for workers were, respectively, New Hampshire, Minnesota, Vermont and Iowa. After Louisiana, the next-lowest states were Texas and Arkansas, along with three states that fared slightly better in a tie: Mississippi, South Carolina and Utah.

Hawai'i tied with Massachusetts for 18th. The 50th state scored high in job opportunities, ranking ninth, but lost points for job quality and workplace fairness.

Massachusetts was also hurt in part by its high cost of living and large pool of workers who wish to work full-time but are stuck with part-time jobs.

The "Decent Work in America" study, released yesterday by UMass Amherst's Political Economy Research Institute, was based on a "work environment index" that compared states based on 2004 data. The data covered factors including average pay; job opportunities; employee benefits; percentage of low-income workers; fair treatment between genders; and ability for employees to unionize.

Those factors were used in ranking states on a scale of 1 to 100 for job opportunities, job quality and workplace fairness. Those three numbers were averaged to determine an overall score, with Delaware posting an 89 and Louisiana a 31.

Hawai'i scored a 65 overall. The state scored a 48 for job quality, 81 for job opportunities and a 65 for workplace fairness.

Texas' next-to-last ranking drew criticism from the state's governor's office and from a Texas economic development official, who said the abundance of small states near the top of the rankings indicates the study criteria may be too narrow.

The study's authors, who expect to update the rankings annually, said their findings were based on the first index to evaluate states' treatment of workers rather than their business climates.

States ranking high for work environments generally enjoyed strong economic growth and low poverty rates, with the reverse true for those ranking low.

"This suggests that anti-poverty strategies focused on creating decent jobs is viable as well as desirable, a finding that is especially pertinent in the aftermath of Hurricane Katrina, whose impact was devastating on the poor in New Orleans," the authors said.

UMASS RANKINGS OF U.S. JOB QUALITY

Rankings of the 50 states and Washington, D.C. in the University of Massachusetts Amherst's "Decent Work in America" study, which compared states' working environments. An overall number was assigned to each state, based on job opportunities, job quality and workplace fairness:

1. Delaware 89

2. New Hampshire 81

3. Minnesota 80

4. Vermont 77

5. Iowa 73

6. Connecticut 72

7. Indiana 71, Nebraska 71, Wisconsin 71

10. South Dakota 70

11. North Dakota 69

12. Maine 68, Pennsylvania 68, Rhode Island 68

15. New Jersey 67

16. Kentucky 66, Missouri 66

18. Hawai'i 65, Massachusetts 65

20. Maryland 63

21. Alaska 60, Washington 60

23. Illinois 58

24. Michigan 56, Ohio 56

26. Virginia 54

27. Colorado 53, Kansas 53, Montana 53, Tennessee 53

31. Idaho 52, Wyoming 52

33. California 51

34. Washington, D.C. 49, Georgia 49

36. New York 48, Oregon 48

38. West Virginia 45

39. Oklahoma 43

40. Florida 42, North Carolina 42

42. Nevada 41

43. Alabama 40

44. New Mexico 39

45. Arizona 37

46. Mississippi 36, South Carolina 36, Utah 36

49. Arkansas 34

50. Texas 33

51. Louisiana 31