I would not consider optimism, self-efficacy and hardiness as components of proactive behavior. Rather, they might be considered as individual characteristics that predict if and how much proactive behavior a person typically shows.
There is good evidence for the role of self-efficacy in predicting proactive behavior (see Parker and Ohly, 2009) and also for optimism (research by Aspinwall) but I am not aware of any research linking hardiness to proactive behavior. It makes sense though because hardiness comprises many aspects that have been linked to proactive behavior. Hope this helps.
Yes, I agree - these characteristics reflect my research (originally for PhD) into people living with faecal incontinence. I am now writing an article for my 10 year follow-up. The participants in my studies who I termed 'Approaching Mastery', are, through their proactivity, enabling adaptation, are described by your components of proactive behaviour. Adding to Sandra's answer, I have been looking into resilience (especially for my 5 year follow-up) in connection with these concepts and would include (health related) hardiness. An article I read recently is: Stewart, D. E., & Yuen, T. (2011). A systematic review of resilience in the physically ill. Psychosomatics, 52(3), 199-209. Although the authors do not mention proactive behaviour, in their discussion, they start by listing its components including hardiness. I also feel that your constructs is appropriate. Best wishes with your work on this - is it for your PhD? Mary.
Mary, thanks for your answer. Yes, I'm planning to write a thesis on this topic, including how proactivity impacts on health and adaptation in people with various mental disorders and physical illnesses