Nature and limitations of psychological research
Experimental psychology typically involves studying the effect of certain stimuli. These can include environmental stimuli in the natural setting (see example: Kööts et al. 2015) to experimentally induced parameters (see example: Williams & Bargh 2008). As it is not always possible to know what exactly happens in the mind nor measure things physiologically (one cannot easily measure happiness or sadness quantitatively), it is common to assess some responses through self-reports via surveys or psychological batteries. Nonetheless, there are glaring limitations that impede such data collection.
A typical psychology battery can consist of hundreds of items (questions) and can take hours to fully respond. In the fast-paced society of today, long data collection times are highly unpopular with participants, resulting in high dropout rates and low sample numbers. A possible solution to this is to increase accessibility and convenience of survey participation using smartphone applications, and in a way that participants can complete them at their convenience (see example app: PsychVey, described in Nguyen et al. 2015).
The other difficulty lies in measuring individual data. Current psychological research relies too heavily on self-reports which are highly subjective and biased (Dunning et al. 2004). These self-reports are clouded by denial, moods, and cognitive dissonance (see example: Spector, 1994). While there are equipment to directly measure some physiological parameters (such as cortisol, see Van Cauter et al. 1996), these resources are not widely accessible to the general public due to the requirement of skilled use. skilled use. Again, with the smartphone to the rescue, it may be possible to leverage on sensors (either in-built into smartphones or peripherally attached) to simplify the skills and make common the ability to collect such direct measurments. This allows individual qualitative data to be collected quantitatively. One way is to use the microphone to measure heart rate (iStethoscope in Apple App Store) for anxiety studies. Such measurements get far more accurate data than self-reports of anxiety, especially if the participants have tendencies to underplay or overplay their difficulties (such as in the case of hypochondriacs).
The final limitation of psychological studies, and also the most important problem, is the lack of diversity in the sample size. It is often only possible to investigate and study a local sample because of the geographical constraints. As a result, studies are often culture-specific and lack ecological validity, making it difficult for the study to be generalized to real-life settings. By using smartphone apps to gather data (this can take the form of surveys, physiological measurements or cognitive responses), data can be collected from across the globe easily and cost effectively, making psychological findings more relevant to a wider general audience. With larger sample sizes that are more diverse, psychological studies may be more reproducible, a problem recently highlighted (Open Science Collaboration, 2015).