[5][6] The proportion of female candidates varied by region: 26.6% in Wales, 26.2% in England (30.4% in London), 25.6% in Scotland, and 23.9% in Northern Ireland.
[7] University College London's Parliamentary Candidates UK project[8] evaluated the background of 2015 general-election candidates (excluding incumbent MPs) from the seven major parties: Conservative, Labour, Liberal Democrat, UKIP, Plaid Cymru, the SNP, and the Greens.
[9] The project found that 26% of candidates contesting the 2015 general election were political professionals (defined as those currently working as advisers, researchers, party officials, trade unionists or lobbyists).
[9] The party with the highest percentages of candidates from a business or commercial background was UKIP (37%) and the Conservatives (21%); the lowest is the Greens (15%).
[10] Tracy McVeigh,[15] The oldest candidate is Doris Osen, 84, of the Elderly Persons' Independent Party (EPIC), who is standing in Ilford North.
[16] Neither UKIP nor the Greens selected a black or ethnic minority candidate to stand in a seat viewed as winnable.
[16] The Green leader, Natalie Bennett, stated that "I would agree that our percentage of BME candidates is disappointing and it's something we very much want to focus on.
[4][note 1] By tradition, none of the major parties stand candidates against the speaker of the House of Commons (currently John Bercow).
[4][6][24][25] Among the minor parties: The Conservatives, Labour, Liberal Democrats, UKIP and Plaid Cymru stood candidates across all 40 constituencies in Wales.
[42][43] Sinn Féin, the SDLP and Alliance stood in all 18; the DUP in 16 (having made an electoral pact to support the UUP in two constituencies); the Conservatives in 16; the UUP in 15 (having made an electoral pact to support the DUP in two constituencies; they also did not stand in North Down against Sylvia Hermon); UKIP in ten; TUV in seven, the Greens in five, and the Workers' Party in five.
[42] In Northern Ireland, the fewest candidates in a constituency was five (in Fermanagh and South Tyrone and Newry and Armagh); the most was 10 in North Down.