A leading US gay organisation has revealed its assessment of the current state of LGBT representation on American network TV and singled out ABC as the best-performing network.

The Gay Lesbian Alliance Against Defamation (GLAAD) released its inaugural GLAAD Network Responsibility Index, a first-of-its-kind report that maps the quantity, quality and diversity of images of lesbian, gay, bisexual and transgender people on network television.

ABC, with shows such as Brothers Sisters and Ugly Betty, received the highest ranking of the five networks.

NBC, once home to Will Grace, ranked fourth, and FOX scored lowest.

“While we have made great strides in the ten years since Ellen Degeneres came out on television,” commented GLAAD President Neil G. Giuliano.

“This report shows where work still needs to be done and which networks are failing to represent millions of lesbian, gay, bisexual and transgender viewers. The airwaves quite literally belong to each and every one of us, and, as such, networks have an obligation to reflect the faces and stories of their viewers.”

GLAAD examined all primetime programming – 4,693 hours – on the five major US networks (ABC, CBS, The CW, FOX, and NBC) from June 1, 2006 – May 31, 2007.

Each hour was reviewed for any on-screen major or minor LGBT representations.

Based on the overall quantity, quality and diversity of these representations, a grade was assigned to each network: Excellent, Good, Fair, or Failing.

ABC received a grade of Good and led the networks with 15% of its primetime programming hours inclusive of LGBT representations.

The CW followed with a Fair; 12% of its programming hours were LGBT inclusive. CBS received a Fair for its 9 percent of LGBT-inclusive programming hours.

NBC was given a Fair for its 7%. FOX received a Failing grade for its 6% of LGBT-inclusive programming hours. No network received an Excellent ranking.

“We know that seeing multi-dimensional, diverse people represented on television changes public perception,” says GLAAD Entertainment Media Director Damon Romine, editor of the report.

“Millions of lesbian, gay, bisexual and transgender Americans fight every day for equality and for the right to live their lives without fear of discrimination and violence. True equality will be in our grasp when network television presents our stories in a fair, accurate and inclusive way.”

Copies of the GLAAD Network Responsibility Index have been delivered to programming executives at the five networks, and the organisation wants further discussions with the networks on ways to improve their LGBT representation.