Advertisements may be framed so as to abuse the confidence of the consumer or exploit his lack of experience or knowledge. They may appeal to superstition or may play unjustifiably on fear. They may contain statements or visual presentations which directly or by implication, omission or ambiguity are likely to mislead the consumer, including claims purporting to be statements of fact.
Advertisements may mislead as to: the qualities of the product advertised (for example, its composition, construction, utility or suitability, or its commercial or geographical origin), the price or value of the product or the terms of purchase; the services accompanying purchase (including delivery, exchange, return, repair and maintenance); the contents and the value of the guarantee attached to the product; the existence of any patent protection or other industrial property right, or medals, prizes, etc; the qualities, the price, the value or the terms of purchase of other products on the market and the services accompanying the purchase of such products; the trustworthiness of statements made by other advertisers.
Scientific terms, statistics and quotations from technical literature and the like may be used without a proper sense of responsibility to the consumer (for example, statistics with a limited validity may be presented in such a way as to make it appear that they are universally true). Advertisements which support some charitable cause may mislead as to the share of the proceeds which will in fact go to the charity. Advertisements may contain references to persons or organizations without due permission, or to competitors and their products in such a way as to bring them into contempt or ridicule, or to exploit the goodwill attached to them, or to imitate their style in such a way as to create confusion among consumers. Advertisements may also be designed so as not to be clearly distinguishable as such (possibly to give the impression of being an editorial opinion in the case of newspaper advertising).
An early 1990s survey of international medical journals found that nearly two-thirds of the advertisements were either grossly misleading or downright inaccurate.
The issue of nutritional, health, ethical and environmental claims in advertising is given special attention by consumer associations, industry, and national and international policy initiatives. In Europe the matter is brought into sharper focus because the European Commission is preparing a revision of Directive 84/450/EEC on misleading advertising. Ensuring that consumers have a high level of health and safety is one of the three principal policy objectives of the Consumer Policy Action Plan for 1999-2001, which implements the general framework of Decision Number 283/1999/EC. This also covers labels and logos, with the aim of obtaining information about whether national systems for verifying claims are in fact functioning and effective in order to protect consumers; and obtaining comparable information about the outcomes of the complaints at national level. Both so-called "on-pack" claims and advertisements of any sort are covered.