The value of remote betting (which includes betting online via PC, laptop, tablet, smartphone, television, etc.) has seen a substan-tial increase in recent years, with football betting and in-play betting being a predominant driver of growth. In-play betting, also known as live action betting in-running betting, refers to the wagering on an event that has started but not yet finished. Here, gamblers have the option to continue to bet once an event has started,and adapt their bets depending on how the event is progressing (e.g., on a sporting event such as a football or cricket match).

In-play betting first appeared towards the end of the 1990s when some bookmakers would take bets over the telephone whilst a sports event was in progress, and has now evolved into a popular online service in many countries. For example, in the UK, up to 25% of online gamblers have placed a bet in-play (Gambling Commission 2016 ). The online sports betting company Bet365 reported that 80% of all their sports betting revenue is derived from in-play bets alone (Jackson 2015 ). The introduction of in-play betting has allowed bookmakers to increase the number of markets available to bet on during sports events, and gamblers are able to place bets based on many different types of in-game activity during the matches. For example, in football matches, it is possible to bet on in-play markets including the match result, half-time score, number of goals scored in the first or second half of the game,the number of yellow cards during the match, and the name of the goal scorers.

The availability of a particular sport and in-play markets varies from bookmaker to bookmaker. Researchers have previously referred to the role of structural characteristics in the acqui-sition, maintenance, and development of online gambling behaviours (Parke and Griffiths 2007 ). Structural characteristics are those features that are inherent within the game itself and include features that are responsible for reinforcement and may in some cases facilitate excessive gambling . These characteristics include, but are not limited to, bet frequency (the number of bets placed within a given time frame), event frequency (the number of gambling events that are available to bet on in a given period), and pay-out frequency (the time between the end of the betting event and receiving the winning payment). 

In-play sports betting has structural characteristics that have changed the mechanics of gambling for sports bettors, as they are now able to place a larger number of bets during a single sports game (as opposed to a single bet on who is going to win). It has been argued that structural characteristics of an event, including higher event frequency betting, are associated with problem gambling. One of the most important differences between being able to place an in-running sports bet opposed to a pre-match bet is that the nature of the market has turned what was previously a discontinuous form of gambling into a continuous one. 

The gambling study literature has suggested that in-play sports betting may offer more of a risk to problem gamblers because it allows the option for high-speed continuous betting and requires rapid and impulsive decisions in the absence of time for reflection. Furthermore, marketing messages promoting online sports gambling have become increasingly prevalent to media audiences. Sports betting is one of the most commonly promoted forms of gambling in many countries,and access to this marketing activity has been associated with sports betting problems. Advertisements often promote online sports betting as being easily accessible, anywhere at any time, using a mobile or other internet compatible device. There has also been a growth in in-play sports betting advertising. For example, within a sample of British and Spanish sports betting advertisements, in-play betting was prevalent in just under half of the adverts. One popular form of gambling advertising is the promotion of wagering inducements. These are often inducements that are promoted during a live event, and it has been suggested that doing so may promote impulse betting, where those placing a bet have an immediate chance to place the incentivised bet via a platform .Inducements promoted during an in-match sporting event have been cited as a practice that may encourage in-play impulse betting intentions.

Gambling companies have been known to promote mobile betting over other forms ofgambling in their advertisements by overstating the illusion of control that gamblers perceive when placing bets via their smartphones. A main cognitive heuristic involved in the maintenance of gamblingbehaviour is the illusion of control. The illusion of control generates an expectancy of success that is inappropriately higher than is objectively warranted. 

In-play sports has the potential to enhance the illusion of control because gamblers are often able to dictate the speed of play, the volume of betting, and amount of money wagered, which may enhance both psychological perception and investments of control over their sports bet placement.Whilst in-play sports betting features (such as the cash out feature) are increasing in popularity amongst online gambling operators and despite the growing body of research investigating the psychosocial and individual psycho-logical factors determining gambling behaviour, much less attention has been devoted to understanding these factors in the context of in-play sports betting and the market character-istics of online sports betting. Therefore, the goal of the present scoping study was to identifywhat (i) has been published on the topic, (ii) empirical studies have been carried out, and (iii)in-play features are currently available to online sports gamblers via an examination of the world's leading sports betting sites.