This week, Iain Duncan Smith has again been talking about the replacement of disability living allowance (DLA) with the personal independence payment (PIP). The key to this reform will be the way its eligibility criteria are used and it is imperative that this is got right - but will it be? Concerns remain. In an interview with the Telegraph, published on Sunday, Work and Pensions Secretary Duncan Smith reiterated his arguments for the planned reform of DLA. For those who have followed the debate, he said nothing new: claims have gone up by 30% in recent years, assessments weren't rigorous etc. However, it should be noted that Duncan Smith's comments did contain some inaccuracies, such as his statement that 70% of claimants had 'lifetime' awards. This is untrue: 'lifetime' awards were abandoned in 2000 and replaced with 'indefinite' awards. In any event, it's not unreasonable for a proportion of people to claim DLA for long periods of time. Rather than "fester" on it, as Duncan Smith put it, many people with learning or physical disabilities will never see substantial improvement in their conditions. While their life and capabilities may improve with help, taking away their benefit and what it enables them to purchase, could see their progress reversed. With this in mind, the focus has to be on ensuring that PIP is as fair as possible and that the eligibility criteria take such things into account. The Telegraph said that PIP may be based on the work capability assessment (WCA), which is used for employment and support allowance. This will send a shiver down the spine of many who claim that benefit. The WCA is widely disliked by claimants, and has been the subject of two reviews by Professor Malcolm Harrington since its introduction in October 2008, yet still concerns remain. The main gripes about the WCA revolve around such things as whether it takes into account the difficulties that people with conditions such as autism face - and the help they need to function. The eligibility criteria for PIP will need to ensure that issue of this kind are properly addressed. While people with profound or complex learning disabilities may have little to fear in these reforms - Duncan Smith says that the benefit will focus on those who need it most - some at the milder end of the spectrum, such as those who currently claim lower-rate DLA may well lose out. Indeed, with the stated aim of getting 500,000 people off the existing benefit, it seems certain that some will be deemed ineligible. This is where the main concerns lie. While the changes may help to cut the benefit bill, people who do lose out could experience serious reductions in their quality of life and in their independence. For example, if the money is currently used to pay for transport to work, it could mean they will not be able get there and would lose their job as a result.  If the eligibility criteria aren't up to scratch, that may result in short-term cost savings for the Government. But, in the longer-term, it could cost more in economic and - more importantly - human terms. Consultations are on-going over the eligibility criteria, so now is the time to get these messages across to Government in the strongest possible terms.