Here is a video describing a beginning method to making astrological predictions with dashas.
Below the video you will find a brief written account of the influences discussed in the video.
Car crash occurred in the afternoon of 9/19/2013. Driver side hit. Witness says native ran a red light. Native does not recall doing this. Was hospitalized with subdural hematoma. Left hospital that evening when relative picked native up and drove three hours back from accident to home.
Vimshottari Dasha running was Sa/Ve/Sa/Ma on 9/19/2013.
From the lagna Saturn as third lord is in the 12th. Losses or hospitalization due to short distance travel. Since this may be the natives fault, due to possibly running a red light, Saturn may give lawsuits since Saturn is negatively impacting the 6th house from the 7th.
From the lagna Venus is 6th and 11th lord in the 12th. 6th lord can show injury causing financial loss. The 11th lord supports by being the 6th from the 6th. Venus is Karaka of vehicles and in the 12th (loss).
From Venus, Saturn rules the 3rd (short distance travel) and 4th (vehicles) houses. Saturn thirsts Venus by being in the same sign.
From Saturn, Mars rules the 6th and 12th and is placed in the 3rd house. Saturn is powerfully thirsted by the exalted Mars. From Saturn, Saturn rules the 3rd (short distance travel) and 4th (conveyances) house. Mars rules the 6th (injury) and the 12th (hospitalization and loss). 3rd and 4th house matters are severely damaged by 6th and 12th house matters.
By transit, on this day, Rahu, Saturn, and Venus were within 1 degree of each other in the sky and within 1 degree of the native’s natal Saturn.
All house lords involved, both from the lagna and then from the dasha and sub period lords are all primarily 3rd, 6th, 4th, 11th, and 12th lords. Combinations of all these lords point to the accident, injury and loss while traveling.
Categories: astrology predictions, horoscope assessment
Asheville Vedic Astrology 
I would like to know if the chart used here is a tropical zodiac?
Yes it is!
What about all the various form of dashas? Are there not a wide variety of dashas depending on different concerns?
Yes. There are many. I’ve found that focusing on one is a good. I mainly use Vimshottari and then the conditional nakshatra dashas if they are present and applicable to a person’s chart.