ValueClick Inc. reported solid first-quarter earnings late Tuesday that beat expectations, but shares suffered after an analyst questioned the company’s business model and financials.

Net income for the three months ended March 31 increased to $19.2 million (19 cents per share), from $18.6 million (18 cents) in the same period a year earlier. The results bested Wall Street’s expectations of 16 cents per share, according to Thomson Financial.

Revenue for the Westlake Village-based online ad seller rose 12 percent to $176 million, also surpassing analysts’ estimates of $170 million.

For the year, the company added that it now expects net income of between 81 cents and 83 cents per share for the year ahead of analysts’ expectations of 79 cents. The previous outlook, issued Feb. 13, called for profit of 78 cents to 81 cents per share. The company reaffirmed its target revenue range of $730 million to $745 million.

However, Merriman, Curhan, Ford & Co. analyst Richard Fetyko threw cold water on the earnings by saying they raised several questions about the company’s business model and earnings quality.

Fetyko advised investors to stay on the sidelines after ValuClick’s media and affiliate marketing units missed expectations, while profit benefited from a one-time traffic boost because of its comparison shopping unit which added $5 million in revenues during the quarter.

“The mystery of this one-time source of traffic and timing raises questions about the source of traffic for all of the comparison shopping segment,” Fetyko said in a note to clients.

Shares in ValueClick closed down 7 percent to $19.77 Wednesday.