Understatement of more than Rs 4 crore had been detected in surveys conducted in doctors premises for 2009-2010,said chief income-tax commissioner S K Jha,ahead of the last date of tax payment on Monday. Jha was addressing doctors at a meeting of the Indian Medical Association,Pune Chapter,was held at the IMA Hall on Tilak Road. The tax regime is very moderate and the department is making increasing use of technology to reduce the interface between the tax payer and tax collector. The Refund Banker scheme is a step towards this, Jha said. Expressing concern over the number of doctors with taxable income who were outside the tax net,he requested the IMA to persuade such members of the profession to start paying tax on correct income and filing income tax returns.