When it comes to self-monitoring kits for hypertension and diabetes, Consumer Reports found big differences in accuracy and consistency. In a recent report, CR suggests that relying on the readings of an inaccurate model could lead to inadequate care.

Seventy-three million U.S. adults have high blood pressure, and 24 million have diabetes. Of those populations, an estimated 65 percent do not have their high blood pressure under control, and 44 percent do not have their diabetes under control.

BLOOD-PRESSURE MONITORS: High blood pressure is defined as a systolic — when the heart contracts — pressure of at least 140 millimeters of mercury or a diastolic — when the heart relaxes in between heartbeats — pressure of at least 90 millimeters of mercury recorded on at least two office visits. In May, the American Heart Association and other medical groups announced that people with hypertension or suspected high blood pressure should routinely self-monitor.

To evaluate 16 blood-pressure monitors, CR obtained approximately 6,000 readings from 57 men and women and compared the results of the home monitors with those obtained by pairs of trained medical technicians who used a mercury sphygmomanometer, the standard instrument for recording accurate blood-pressure readings.

TOP BLOOD-PRESSURE MONITORS: CR found that four upper-arm-cuff blood-pressure monitors were more accurate, overall, than wrist monitors. Four automatic upper-arm-type blood-pressure monitors were rated excellent for accuracy and test time. They provided accurate blood-pressure readings in about 30 seconds and can also detect an irregular heartbeat. They are the Omron Women’s Advanced Elite 7300W ($100); CVS by Microlife Deluxe Advanced 344534 ($100); Omron HEM-711AC ($90); and ReliOn HEM-741CREL (Wal-Mart,) a CR Best Buy at $40.

Although the Omron Women’s Advanced is marketed to women, it included a large-size cuff and can also be used by men. The ReliOn is comfortable and has multiple user memories, but if a large cuff is needed, it must be purchased separately for about $10.

BLOOD-GLUCOSE METERS: With Type 1 diabetes, the body loses its ability to make insulin, the hormone that helps convert sugar and other food into energy. With Type 2 diabetes, the body makes relatively too little insulin and is also resistant to it.

Choosing a meter that provides accurate and consistent readings is essential for many people with diabetes who need daily insulin injections. Inaccurate or inconsistent test results could possibly lead to too much or too little treatment, including dangerously low blood-sugar levels.

The following four models were named CR Quick Picks, as they scored well in accuracy and consistency: OneTouch UltraMini ($20, $1.14 per strip); Ascensia Contour ($80, $1.10 per strip); ReliOn Ultima (Wal-Mart), a CR Best Buy ($9, $0.44 per strip); and Accu-Chek Compact Plus ($73, $1.10 per strip).

While the OneTouch was the only blood-glucose meter receiving an excellent rating overall, the Ascensia and Accu-Chek were rated very good choices, as was the ReliOn. All four models delivered readings in about five seconds.

HOW TO CHOOSE A SELF-TEST KIT: Use CR’s Ratings. Pick a top-scoring model that has features that will make testing easier, such as a blood-pressure monitor’s ability for more than one user to store readings.

* Consider cost. Sometimes blood-pressure and blood-glucose monitors can be purchased at a discount. Glucose test strips can cost as much as $1,400 a year if testing three times a day, so be sure to consider their cost when buying a meter.

* Check the fit. Make sure the blood-pressure monitor has a cuff that fits the upper arm.

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