Physicians' groups affiliated with Sturdy Memorial Hospital received high grades overall in a new statewide ratings system now available to consumers on the Internet.

The ratings for Sturdy Memorial Associates, a collection of group practices in the Attleboro area, showed performance levels above national and state averages in most of the areas of care rated by Massachusetts Health Quality Partners, a network of health care providers, insurers, consumers and agencies.

The data evaluates how well 150 group practices throughout the state performed in 15 areas of care for depression, asthma, heart disease and cholesterol management, adult diabetes, pediatrics and women's health.

The system awards from one to four stars for each area, granting four stars if the performance was above both the national and state averages and in the 90th national percentile, three stars if two of those targets were met, two stars if one was met, and one star if performance was below both the national and state targets.

Sturdy Memorial Associates scored either four or three stars in 10 of the 15 categories. It scored two stars for follow-up appointments for depression and for chlamydia screening, and one star in only one category, asthma medication for adults.

Overall, Massachusetts doctors did as well, exceeding the national averages in most categories.

Dr. Daniel Pietro, director of medicine at Sturdy Memorial Hospital, said the ratings are good news for health care locally and statewide.

`` Massachusetts is leading the way,'' he said, and Sturdy Associates are at or above the average in most areas.

A low rating, he said, `` makes us pay attention,'' and assess if improvements in practices are needed.

The data, now available at www.mhqp.org, is one of a series of steps being taken to rank health care so doctors can improve their practices and so consumers can be informed and make better choices.

Yet even the network admits that the ratings system has its limitations.

It looked only at medical groups and not individual doctors, and included only patients served by five Massachusetts health plans but not those who have no insurance, or those who are covered by Medicaid, Medicare or other insurance companies.

The results can also be affected by variables such as the electronic records systems used by the medical group, and the faithfulness of the patients themselves in following their doctor's recommendations.

Pietro also noted that a limited sampling of patients was used, so the ratings can be easily skewed. Other factors also come into play, he said.

One example is the two-star rating the associates received for follow-up appointments in treating depression. Part of the issue, Pietro said, is the availability of doctors for psychiatric evaluations, and efforts are being made to bring more psychiatrists to the area.

But he said the system does serve as a tool for physicians to evaluate the care they provide, and as a way for consumers to be informed so they can ask better questions.

Yet, Pietro advises caution.

`` This kind of reporting needs to be looked at carefully,'' he said. `` When you see a group not performing well by these measurements, you need to understand why.''

Patients trying to make comparisons may also be overwhelmed by the amount of data.

`` The flood of information is as confusing as it might be helpful,'' Pietro said.

Even more information is on the way.

Massachusetts Health Quality Partners plans to issue more reports in coming years, including some that will assess specialists and primary care doctors.